0 casualties are unclear at this time. we will provide additional details when we can. we also learned moments ago that president biden has been briefed on that explosion outside of kabul airport. a white house official tells cnn. and we are waiting on a pentagon press briefing which will happen in about 30 minutes from now. the back ground on this, as you look at a live picture from the kabul airport, that in recent days and yesterday we reported the u.s. has been very concerned about a credible threat stream about potential terror attacks targeting the gates to the airport and the crowds around those gates. the u.s. believing that terror groups had both the capability and the planning to carry out such attacks. there is still no attribution for these attacks or as we said, any confirmation about casualties. we have our reporters covering the story. let's begin with nick paton walsh in doha. we see now a confirmed attack. >> -- only the families of the u.s. serve men concerned about who may have been on the airport at the time and also for the many afghans waiting outside. we don't know the reason behind this at this stage. it is an explosion. we haven't clarified precisely there are many things moving in that area. could be crowded areas so other reasons why there could have been a blast but it will play directly into fears of a possible attack. let me just tell you a little bit about where we think this might have occurred. in the out skirts of hamid karzai airport. no precise location. but there are many afghans waiting at key gates. there is one called abby gate and northeast gate and northern gates as well. people crowd to them. they're often huge metal doors essentially, i've heard people banging on them. it is an extraordinary noise of desperation and that is where we've seen the stand-off between afghan and u.s. marines and the crowds down below. the traffic is often blocked around there and i've seen video and heard reports that the taliban have been involved in using their presence as a sort of crowd filtration, vetting who is allowed to approach the gates and even more involve further away from the airport, further down the airport road. so it is unclear where this blast has occurred. it is certainly i think the worst news for anybody observing the situation closely. but it is sadly will most likely have fed into an area that is quite heavily populated. we've seen images of thousands, it seems, of afghans despite the news the gates are fully closed. there is at this point no way on unless you are essentially escorted or entry on to the airport is arranged by prior coordination by the taliban and the united states and even people who have half of that circulating around the base in buses this morning. people have still gone to the gates in large numbers. they've stood, i've seen videos of them standing in sewage water in the ducts along there below razor wire dangerous in the crush holding up pieces of paper demanding to be allowed in, making they're case as to why the nato allies should bring them on to the base. now obviously for those who have a distaste for the u.s. presence, they prove a target but coming out of the base there have been u.s. service members in the past, unclear what has occurred here but it is a sensitive and delicate target. so densely populated. >> no question, nick paton walsh. so let's remember what we have learned at this point. explosion outside of kabul airport. at one of the gates there. where there have been a number of crowds trying, clamoring to get in on to get on a evacuation flight out. our latest information it appears to be a suicide attack. that could be consistent with the kind of attacks that u.s. officials have been concerned about in the hours and days leading up to this. as we reported yesterday, a credible threat intelligence stream that the u.s. had about plots, planning and capability to carry out an attack targeting exactly a gate like this and exactly a crowd like this that has been gathering at these gates. i want to go now to sam kiley. he was on the ground until just yesterday morning among the journalists taking out of the country in part because of safety concerns. sam, this was the concern and the sad fact is the pentagon now confirming such an attack. >> reporter: yeah, the situation on kabul international airport for several days until i left yesterday evening, in fact, jim, was extremely tense. because they did have this very active ongoing intelligence with some precision. this he were anticipating a spectacular attack. they were anticipating an attack almost certainly against the crowds gathering outside of the gate. and they anticipated that it would be so-called isis-k, isis group behind it. we don't know yet officially in any great detail the providence of this bomb but all of the fingers will be pointing toward isis-k and the only organization jim in the world that has an interest in committing this kind of atrocity. because it does three things. it intimidates the afghan population, which is very much an isis tactic or even strategy. it embarrasses the taliban who had got a security deal, they were effectively running security in their own way and filtering out afghans, counter to american policy. but they were working with the united states. and then you have the united states running security for that multi-national coalition effort to get as many people out before they have to start withdrawing the themselves. this is a very vulnerable time. and the locations as nick said, he laid it out accurately, there are these bottlenecks that present themselves as fantastic targets for those cynical and violent terrorist organizations, probably the world has ever seen. they want the publicity and the attention. they want to humiliate both the taliban and the united states. and that is what they're trying to achieve with the atrocity of this nature. and on top of that they will make it harder for the last refugees to get out. >> sam kiley, as sam was speaking there, you could see that and i again i want to remind you this is a live picture from the kabul airport. what we saw crossing the screen was a chinnock double rotor helicopter, that is the clouds of smoke rising that the rotors brought up. hard to read in to what that is but that is activity at the airport and we'll bring you details more as we hear more about casualties, if they were casualties, who among those casualties, the pentagon confirmed an attack at gates and it is our latest information that this appears to be a suicide attack. that could be consistent with the tactics used by a number of terror groups who should be clear in afghanistan, though i should note that the particular concern leading up to this moment, this specific intelligence stream that we reported yesterday, focused on the group isis-k or islamic state corizan. many groups making a base home in afghanistan. let's go back to kylie atwood. kylie, i know you've been working your sources on this. are you learning any more details about the exact location of this attack or the possibility of casualties? >> reporter: yeah, jim, what ware learning is that this attack happened at one of those entry gates. that you guys have been discussing. these entry gates have been swarmed by afghans over the last few days, over the last ten days frankly trying to get into the airport. that would explain why we are hearing there are afghan casualties as a result of this explosion. now, we are told that this explosion looks like a suicide attack. that it was something that one person potentially going in, but we're looking to learn more about that. but significantly these gates have been closed largely for the last few days. as the united states has prioritized getting in americans. but the afghans have still been in large crowds outside of these gates. that is made the situation at the airport as the u.s. government has been tracking this isis-k threat, incredibly dangerous. and we heard just this morning from the top u.s. diplomat on the the ground in afghanistan who wouldn't talk about the threat streams that the united states was picking up. but used the word imminent to describe the threats that they are seeing that are possible. of course, what we're seeing now is something that they were likely tracking generally speaking. so this is going to be an incredibly quick evolving situation. we're looking to learn more. were there any casualties, was anyone hurt on the u.s. side as of now, there are no u.s. casualties that we are told. but we'll also watch to see how this impacts the evacuation effort. the united states is still flying americans out of the country. they warned those americans to stay away from these gates, just yesterday because of the threat stream that they were seeing. but right now what we're learning is that this was at one of those entry gates into the airport and it is suspected to be a suicide attack. >> kylie atwood at the state department. and if you could put the map up on the screen. this is a live picture at the airport looking toward the flight line, the runway there. the main entrances to the airport for civilians are on the south side. the civilian side for entry to the airport and that appears to be at one of the entry points where this attack took place. as i mentioned, it is our latest information it appears to be a suicide attack. that consistent with the tactics of a number of terror groups operating in afghanistan. it is also consistent with a warning, an intelligence threat stream that we reported on yesterday about plots and planning and capabilities for such an attack in and around the airport that the u.s. became aware of. that particular warning focused on one group, isis-k. there are a lot of bad groups and bad guys running around that country right now with capables to do something like this. john harwood is at the white house where we learned a short time ago that the president has been briefed on the attack. beyond that, does the white house have a reaction to this and do they have any plans to respond? >> reporter: well, the question is going to be how serious the impact of this event has been. important to recognize that we still don't know the gravity of this attack, assuming it was a suicide attack. what the impact was and how many casualties there were on the afghan side or the american side if there were any and the scale of that impact would likely dictate whether or not the united states feels compelled to respond. but this is the nightmare scenario. this is the kind of nightmare scenario that the administration have been worried about as they get to the end of this evacuation process. that vulnerability would be heightened as you had desperate people trying to to get to the airport crowding around the gates and that is why they've tried to encourage people to leave the airport unless authorized to come in. but this is precisely what president biden has worried about. of course, over the last couple of weeks, we have had up to this moment no reported u.s. casualties. and we've had no mass casualty events involving afghans at the airport. has this changed that situation? that is a question that we simply can't answer now. the president may know the answer because he's been briefed and has got access to information that we don't. we're in a wait-and-see mode. and it is possible that the pentagon at that 10:30 briefing will be able to lay out more detail about the scale of the attack and we'll see if the white house has anything to note as well. >> i did see a c-17 taxiing on the runway. we'll continue to monitor and see if that is an indication that flights continue despite the threat. what we saw a few moments ago when was a chinook double rotor helicopter flying across the screen. barbara starr is at the pentagon. is there any new information about what happened here, specifically about casualties. >> reporter: i think what don said is the operative word at the moment. somebody may well know but here at the pentagon they are not publicly saying anything about the possible of casualties. and i think it is very important to sort of take a deep breathe here and remember that there are u.s. military families who know their loved ones are serving at airport who are watching every minute of this and they want to get word about what has happened and if any of their loved ones are in jeopardy. just like the afghans who are at the airport. they're families are going to want to know if their loved ones have been hurt, wounded or even killed in this attack. a lot of people, the world's eyes focused on this airport and a lot of family members on all sides wanting to know what is happened to their loved ones. it is going to be important to remember that the pentagon has very strict notification procedures when any kind of potential, and we don't know yet, mas casualty incident happens. so we want to be very cautious about all of this. we simply have not yet had word from the pentagon. if, if there are injuries to u.s. personnel, there is medical treatment capability on the the airfield. the u.s. military doesn't go anywhere without its medics. but it is always a question of whether they will have to airlift people out of there if, and it is a big if, if there are serious injuries. so this is something that we'll be watching very closely. we're getting some initial indications that the 10:30 news conference scheduled here at the pentagon obviously may float -- may be delayed until later in the morning as they continue to try to gather information. what we know is from kabul to tampa, florida, the military headquarters for middle east operations, to here in the pentagon, meetings are continuous, phone calls are continuous as they try and gather information about what happened. >> yeah. listen, in situations like the military has priorities. one, make the situation safe. two, treat any injuried and do notifications as well. these are things we'll have to wait for to get more details. but let's tell you the details we know now. explosion outside of kabul airport. one of the gates. the gates you've been seeing pictures of in recent days with throngs of people trying desperately to leave the country. sadly the concern had a been leading up to this that terror groups including isis-k would target such gates, such crowds with the exact attention -- intention of creating fear. that is the credible intelligence leading up to this moment. our latest here on cnn is that it appears to be a suicide attack as well. we'll bring you more information as we get new details. i want to go now to sam kiley who only 24 hours ago was along with other journalists vakevacud in the country because of concerns about risks just like this one. as you're watching this unfold here, tell us what your reaction is? >> reporter: i think, jim, it is got a sense of tragic inevitability because of the lay down there, the security lay down bheen means that yes the taliban are patrolling and people walking around with weapons as the british and american military withdraw, there are fewer and fewer people to be on security. they won't have reduced security on the airport perimeter but there are less and less people around to monitor this situation. and in any case, very little they could do about it. if somebody walks in with a backpack and manages to sneak through and detonate a suicide bomb, that is frankly something that was top of anybody's mind a week ago. when you get large crowds like this, isis-k would see that as a target of opportunity that is almost irresistible given their agenda and clearly very acive and sadly no capability to -- [ inaudible ] and now the issue is scale. they love scale, isis. they love to be able to cause carnage on the the most graphic level to humiliate and embarrass the two key enemies which are the taliban and the united states. the taliban have been fighting isis and killing them in large quantities whenever they rise up because they want to dominate the islamic space there and because they learned their lesson of having given safe haven to al qaeda and have been working very hard, perhaps so much on emass kul ating al qaeda, but they have been working hard to stamp out the ultra violent brand of isis started in syria and started acrass afghanistan and trying to get a big publicity stunt if it is isis-k. it is also a very easy area to do a large amount of damage. the blast walls mean if you're close to it, you could almost magnify and channel if you have blast walls on either side of routes which for example exist on the way to the abby gate. that is a canal and a road that have -- the road has blast walls on other side so you could direct the blast up and down the road. there is nothing going out to the side. you get ricochet effect. so very deliberate tarngeting here and clearly something was imminent and now it seems to have happened, jim. >> the sad facts on the ground. sam kiley, thanks very much. our kylie atwood is at the state department as we continue to monitor news from kabul that continues to be a live picture there, an explosion at one of the gates to kabul airport where crowds have been gathering to get on, hopefully try one of the evacuation flights, our latest information is this appears to be a suicide attack consistent with intelligence about a threat in recent days, a threat to the airport. we do not have any confirmation of casualties and who would be among the casualties. kylie atwood at the state department, what is latest you're hearing there. the state department just yesterday warned americans away from the kabul airport specifically because of terror threats to the airport. >> reporter: yeah, that is right. just this morning the top state department official in afghanistan warned of an imminent threat, right. we know that yesterday they told americans to stay away, to leave the gates at the airport if they were there trying to get into the airport. of course to get on to these evacuation flights. it is good news that the united states put out that alert for americans frankly because it means hopefully thatsy lot of the americans that were there left. but the reality on the ground is that we have seen a tremendous number of afghans surrounding these gates, where we are reporting that this explosion happened. so what that means is that even with a suicide attack like this is suspected to be, you could have a large number of casualties. now we don't know how many afghans have died in this explosion yet. that is something that we're still trying to learn and i think it is fair to say that all of the government officials here at the state department, at the pentagon, at the white house are all trying to gather that information because this is such a fast-moving case scenario. this happens just recently. but the bottom line also is what does this do for the evacuation efforts for the biden administration? we have heard the president say he wanted to speed up the evacuation efforts by august 31st to get out because of the isis-k threat streams that they were picking up on the ground, jim. >> kylie atwood at the state department. as kylie was speaking there, and again this is a live picture of the flight line at kabul airport, you could see a flight taking off. it appear be one of the c-17s that has been the work horses of the evacuation operation. that potentially hopeful sign that they're able to continue the flights despite this attack. remember, in these situations, they start with securing the situation, taking care of the injured, getting word out and then moving on to the mission at hand. joining me now is someone to discuss this with a great amount ever experience, lieutenant general h.r. mcmaster, and long history of commanding forces deployed as well. h.r., good to have you on this morning. thanks very much. >> hey, jim. good to be with you under these terrible circumstances. >> absolutely. tell us in your view the significance of this. this had been the fear. we knew the airport was a target. now it appears that terror groups have been able to carry out an effect. what is the potential effect on this of the evacuation operation? >> well i hope it has the opposite effect of what is intended. what the intended effect is to accelerate our departure and to him ihumiliate us. i think that the opposite fact is an end of our delusion. maybe there is a bold line between the taliban and al qaeda and the haqqani network and isis-k. haqqani is in charge of security in kabul. he's the number one hostage taker of americans. and the number one mass murderer of afghan civilians. those are the two principal tactics that they brought to the jihadist echo system and they are the bridge between al qaeda and taliban. so maybe we'll start being serious again. i think that we've exuded extraordinary weakness and that invites these kind of attacks. >> let me ask you this. the troops have already begun to leave. the deadline has been set and the president is sticking to the deadline but that deadline is when the last light is turned off in kabul by the u.s. forces that the evacuations have to end before that because, well you have to get all of the troops off the ground. is there any wiggle room, flexibility for the president here to extend that deadline, to get more people out, both americans and people who served with americans? >> i think the question is what is the mission. is it just following through on the surrender and withdraw or is the mission to get out all americans and get out the afghans at grave risk buzz they've helped us and tried to help build a better future for thur country. if the mission is the latter, then the military can do that. that is our capability. but can we muster the will to do that? what is the mission. it is f withdrawal, then we'll see a humiliating end and a fast forward from the humiliation that evoked images of saigon in 1975 to images of 1979 and a hostage crisis. that is what you're going to see if the mission is just to get the hell out. >> as you know, it was president trump who noeegotiated with the taliban and agreed to a withdrawal day this year. were biden's hands tied by that agreement or could he simply have reversed it? >> no. i'm telling you, that is not the original sin but that is one of the many sins was the capitulation of february of 2020 negotiated by someone still representing the united states after all of the humiliations. how is that the case. they could have reversed this. i don't believe that the president's hands were tied and they're not tied now. why not withdrawal cal izad. and if there is another attack like this or if if you interrupt our evacuation they could be willing to impose those costs. it is a question of will. and as we go further down the path your options get fewer and fewer. and especially if the mission is just to get out. what do you really expect our military and our diplomats on the the ground to do, right? >> fair question. and for the many people and i've spoken to some and i'm sure you have as well. afghans who serve the americans want to leave, have tried to leave and were blocked from leaving. final question if i can, because of course part of this story is the quick capitulation of afghan security forces and the government, ashraf ghani fled on a plane as this was falling apart. does the u.s. military share responsibility going back several years for misleading the american people as to what the u.s. had built there in terms of a credible afghan security force and a credible afghan government? >> well, i'll tell you, jim, in my experience we were very candid about short comings within the afghan national security forces and part of the design was a sustained commitment by the united states. helping them with their asymmetrical abilities, the air power capabilities that were different from the talibans capabilities which is unscrupulousness, and brutality. and so we pulled the carpet out from under them and it was most important is we delivered a series of psychological blows to them. we told them you're not party to this negotiation with the taliban. we entered into a capitulation agreement. we told them we're leaving. you're going to lose all of your support. we forced them to release 5,000 some of the most heinous people on earth who went back to terrorizing the afghan people. so the psychological blows that fell much harder on afghans than even the physical blows that the taliban could have delivered you know what they did with the february 2020 capitulation and president biden's confirmation of that, they went around to district chiefs to provin shall leaders and to afghan army and said here is your options, accommodate with us or we kill your family. what do you think about that? and so that is why you saw this rapid collapse. i think it was completely predictable. >> please stand by. i just want to update our viewers who may just be joining what we know about the situation in kabul and an explosion confirmed by the pentagon outside of kabul airport. it appears based on cnn's reporting to be a suicide attack and one targeting one of the gates of entry to the kabul airport where many afghan civilians but also notably american citizens and green card holders have had to use to access those evacuation flights. and by the way, to get that access has been very difficult. the taliban has been denying many people from coming through but also concerns about an attack just like this led the u.s. embassy in kabul yesterday to warn americans away from going to entrances and gates to the airport because of the threat of a terror attack just like this one. the pentagon has not confirmed casuals yet. it is a question we continue to ask them. looking at that map there, just so you know, it is on the south side of the flight line where we believe this attack took place. and a few minutes ago we did see at least one u.s. military jet take off. the possibility that these evacuation flights are continuing. we should also note that in the moments and days leading up to this, that the u.s. had a warned it had intelligence about a threat to the airport. h.r. mcmaster, that particular warning was about isis-k, as being the one targing the airport. but the fact is there are many terror groups operating inside of afghanistan today. the taliban among them. al qaeda and many thousands of fighter as cording to the u.n. now flocking to afghanistan to join the groups and to train with the groups and make it what it was before 9/11, a terror haven. what does that mean for the security of the united states to have a terror haven like that in afghanistan and does it put us sat risk again of what we saw 20 years ago, a group like al qaeda, plotting attack on the u.s. homeland? >> absolutely. and it puts us at risk of what we saw just six years ago when isis took over large swaths of syria and iraq and then became the most destructive terrorist organization in history. conducting nearly 200 attacks internationally. many of them in europe. shooting down a russian airliner. so this is what we're facing. and this is what happened when you surrendered to jihadist terrorists. you may hear this is isis-k, these exist in eco-system across afghanistan and in which they share people and resources. khanny is the central figure in al qaeda. this is a myth that the taliban is separate from al qaeda and the other groups. would you not be surprised if isis-k was used as a cutout for the taliban so they could humiliate us on the way out and continue to play us. because i don't think they think we're serious people. so our weakness has encouraged them to be emboldened and they'll have access to resources that will make them extraordinarily dangerous as well as the ability now to say, hey, look, we're winning. we've established the islamic emirate in korazan. once they took over territory the size of britain in iraq and in syria. and then we had to go back, jim. so now i would just ask, what was it worth it really? what was a better outcome? a sustained commitment of a few thousand u.s. troops who were continuing to bear the brunt of the fight or the catastrophe we're seeing now. we have this end of wars but this is an endless jihad against us and if we don't acknowledge that we're putting ourselves at extraordinary high risk. >> and with terrorism is victory equals recruiting. when isis took over portions of iraq and syria, it was massive magnet for recruits already leading to a magnet for terrorists from around the world. thank you so much for joining us. i want to up dapt you because an alert has gone out from kabul following this apparent attack at the kabul airport. it said the following that u.s. citizens who are at the abby gate east gate or north gate, these are several main entry points to the airport for civilians should leave immediately. they go on to say there has been a large explosion at the airport and there are reports of gunfire. u.s. citizens should avoid traveling to the airport and avoid airport gates at this time. that is two new details frankly in that statement. one that it was a large explosion and two that there are reports of gunfire that followed. often times in plots like this, you have a explosion and then a follow up of gunfire. -- u.s. forces at the gate as well. again, that is what we know at this point. we don't know at this point how many casualties and who are among those casualties, but we have asked both the u.s. military and the u.s. marine corp and the pentagon, we'll continue to. want to go back to sam kiley. he's at the airport until yesterday. evacuated with many other journalists exactly because of threats of an attack like this one. sam, i know you continue to speak to people on the ground there both afghans and members of the u.s. military. what are you learning now? >> reporter: well it is very unclear indeed, jim, exactly what has unfolded. but we do know that isis-k was conducting in western intelligence services had an imminent plot. did believe that it would be directed at crowds gathering at the gates and it would be a suicide attack we don't know yet whether it was but in the alert from the u.s., they are saying that it was a substantial explosion and additional gunfire. social media has fired up with photographs seeking to verify if people have been injured there. we are still working on trying to find out the exact location of this. but this in all probability, particularly if it is an isis attack is a complex attack. reports of gunfire and there have been reports of gunfire also in advance possibly of this attack. now this is known as a complex attack. isis and terrorists around the world have a system of bombs followed up by secondary explosions very often or gun attacks which intended to increase the level of carnage and sow even greater panic. so the advantage for the coalition forces is there doesn't appear to be any penetration of the base security. that that is remaining rock solid. so in all probability the evacuation or the draw down of coalition troops will continue. but this explosion has meant that a number of countries are ceasing their evacuations notably belgium and holland have announced they will not be conducting any more evacuations because they don't want the people there evacuating coming to the airport in a similar way that americans have put out a note saying please don't come to the airport. precisely because of the danger of these secondary attacks. it is a target of opportunity, it is very obvious that isis-k was likely to conduct this. i've just been in communication with a very senior nato general who said i'm surprised it took them this long. just because they were there, the opportunities were there. this will be a serious blow to the taliban's intended public relations to pose as a nation in -- a nascent nation capable of delivering security and taking its seat in the firmament of other nations and capable of negotiating sufficient security to allow this evacuation. because whatever else this is, it is a failure of taliban securities. taliban security that was supposed to be having its ring of steel around the airport. the number of people trying to evacuate are way down because they have said afghans can't go to the airport. they're not allowing the afghans through but somehow, a suicide bomber or some kind of delivery device was able to get through, jim. >> sam, thanks so much. and stand by for a moment because we do have new information in to cnn. from a pentagon spokesperson john kirby. he said the follow, we can confirm the explosion near the abby gate of the kabul airport has rultsed in an unknown number of casualties. we'll continue to update. not specifying there whether the casualties were afghans or others. but confirming that there is an unknown number, plural, of casualties. one piece of important information again that sam noted there, is that it appears that flights for evacuation are continuing. at least one. we saw one c-17 jet take off during our air. that is significant. if they're able to continue, that would mean they could contain a security cordon around the airport. but an attack was able to take place at one of the gates. kaitlan collins is at the white house. do we have any other reaction from the white house or any indications of changes to plans? >> reporter: there are changes that are already happening we believe reflective of the breaking news. they canceled the coronavirus briefing, it was supposed to start a few moments ago. we'll see if it changes. more things on the schedule here at the white house because this morning the president was briefed at about 9:15 in the situation room but the national security team when the reports of the exposition were just breaking so the president has now been briefed on that. we are told, and we saw the officials including the defense secretary and the secretary of state arriving here about an hour and a half ago. we are scheduled to see president biden in about an hour from now because he's meeting with the new prime minister of israel in the oval office and reporters are scheduled to go into that event currently. we'll see if the president provides any update at that point. officials are still gathering information right now and we're relying on updates we're getting from the pentagon spokesperson but i will say this is the president's biggest concern. and this is when there was a lot of push from other world leaders and from democratic lawmakers to extend that deadline of 8/31 for the u.s. to remove all troops from afghanistan. this is the primary reason that officials were going to the president and saying this isn't a good idea to extend this because they fear the longer the u.s. is on the ground, the more likely of an attack like we're se seeing could happen. and there must have been new intelligence overnight given we saw the state department update their alert to u.s. citizens still in kabul telling them if they're outside of the main gates to get away and to go home and go back to where they were staying and not remain outside of the gates like you had seen so many hundreds of thousands of people doing. and that is something that seems to be reflected in intelligence from other allies including australia, including the united kingdom who similarly updated their alerts warning about the threats. and you reported on it yet. so clearly there was a credible threat behind this. this is what led to this to this morning. we're waiting for president biden to comment. >> we have barbara starr at the pentagon. what are you learning? >> well this is all still evolving very rapidly. but now cnn has three officials saying that there are u.s. personnel wounded in this attack at the airport in kabul. officially the pentagon is sticking to the word that they are -- they have an unknown number of what they call casualties. but we are led to understand from three officials that at least some u.s. personnel are wounded in this. there are indications, of course, of a large number of afghan people wounded in this attack. so the information is very raw, very rough coming in. we expect a briefing from the pentagon later this morning. and of course as we have discussed, the most urgent thing for the u.s. military will be to get medical care to any of its personnel, state department personnel and any u.s. personnel that may have been wounded in this attack. get them medical care, get them med evaced out of there to hospitals if their injuries are that serious that they need that sort of level one trauma care. they will have to get them med evaced out of there as fast as they can. they have some minimal capability on base and to try to assist if at all possible with the afghans. but again, the word is -- the words are very rapidly evolving here. these are very first reports. nonetheless three officials telling cnn there are some u.s. personnel wounded in this attack, jim. >> as you well know, med evac -- [ no audio ] we did see a chinnock helicopter flying across the screen at that side of the airport soon after this attack. but go ahead, go ahead, barbara. what would be next steps then? >> well you know, you raise the key point. i mean, after 20 years of war in the united states, military medical care, it is worth remembering, has advanced to significantly on the battlefield. the first responders generally are helicopters at the point of impact. they have trained medics on board. they even have -- they have developed over the years extensive ability to stop bleeding on site. they have especially treated bandages, especially treated equipment to stop traumatic bleeding if that is what is happened. and now we know that over the years army, marines, medical and military personnel, they all have basic medical training but many of them have advanced medical training in this type of trauma care. and you're right, jim, the u.s. military doesn't deploy anywhere in the world without that kind of care. even special forces these days often deploy with surgical care. so there should be some very readily available care for them to be assessed for the initial treatment and to get those med eva evac airplanes in there. move them back to kuwait and qatar and to the hospital in germany if that is required. we're getting a little ahead of ourselves. >> understood. >> but we do know that the u.s. military moves with medical care all of the time. >> they do. and it is run reason why we've had relatively low death rate in combat in recent years. huge number of injuries that in the past folks might not have survived from. barbara starr, good to have you at pentagon. stand by. i do want to re-up for our viewires. in the last few minutes we have learned that there are u.s. personnel among the casualties from this attack on the kabul airport at a gate to the kabul airport that happened just in the last hour. the u.s. embassy has just put out an alert to americans remaining in kabul that a large explosion took place. that there were reports of gunfire that followed that could indicate what is known as a complex attack, where you have multiple means of attacking, causing casualties and we should note as well as we reported yesterday that there was credible intelligence about the risk, plotting, planning capabilities for a terror attack exactly at one of the gates at the airport. u.s. have been very concerned about that in recent days and have been warning u.s. citizens away. sam kiley left the kabul airport yesterday with a number of journalists in part because of that terror risk. you saw and are aware of some of the medical facilities available there to treat it injured. you could describe them? >> reporter: well, in addition to the 82nd airborne medical capabilities which would have come in with the deployment is a brigade of naval officers and all of that there, the americans will have their own structures. but on top of that there is a norwegian military hospital there by doctors an all specialists in exactly the sorts of surgery that exist sadly specialized out of afghanistan. it is a fully pledged building, not a temporary military hospital. there are four intensive care beds. there is a ward with capability of looking after people. there are four operating and scanners and everything there that anybody would need as long as this is not a mass casualty event for the coalition. so the structures are there in terms of the u.s. military, but in terms of the coalition. i'm not sure which -- nobody would know which direction any kaz casualties will go and nor do we know if these are u.s. casuals. the abby gate is next door to camp barren which is the british base for the filtration of a huge number of evacuees. it is a little bit outside of the main area of the airfield. and if i could describe it slightly, the abby gate is on and is precise as i'm describing, there are blast walls either side of the main road leading to what is called abby gate. you turn to the right, effectively you get into camp barren and you turn left you get into the main airfield and that is a crossing point being used by the military and also by evacuees so it was very much a focus of the efforts by afghans in particular but also members of the international community trying to get out of afghanistan, for getting into the air base. so one of the preferred targets for a group like isis-k. and then on the walls above it, on the perimeter, it is guarded on the airfield side by americans and on the british side by brits. the brits have been scaling back operations and trying to find out exactly whether or not camp barren still exists as a british base. but there were multi-national forces from all over the world in that area guarding the perimeter. not just americans. but this is clearly a major blow to them all. particularly to afghans but also to the coalition, jim. >> no question. and a demonstration of what has become an odd reality in recent weeks with the add vent of the u.s. withdrawal and that is that the taliban controls not only access to the airport for many americans, but also afghans who work for americans. but it also in effect controls security around this airport which is the one exit point, the one remaining exit point from that country for those who want to leave. i do want to play some video that we had live on the screen a short time ago following the attack, following this explosion and that is a u.s. military jet taxiing down the runway and taking off. and an indication at least in that flight that at least one evacuation flight was able to get off after this attack, perhaps a sign that the operation can continue. you see the plane taking off there. we also have nick paton walsh in qatar where many of the evacuation flights have been heading. on your end, and you've seen thousands come in there in recent days, tens of thousands in fact, any indication to whether flights are still heading your way following this attack? >> reporter: as you've shown, the jet there doesn't appear to be ceasing operations at that key evacuation runway. and if you are dealing with a threat like that, the more of them and the afghans who they are trying to help, you could keep flying off that base. provided you're sure that the air space and the runway itself is secure. now we have known that the capabilities of the insurgency have developed over time. but i think that is all kind of baked into a u.s. operation on an airport like that in terms of defense moving forward. so you would imagine that there would have been a pause, some moment in which they locked down, took stock of what necessarily has happened. but the question now of course is what happens to the remainder of the evacuation operation, indications that it may be destined to go until the end of tomorrow in its large scale. the problem here is that this -- if it was abby gate and it does appear that there was a lengthy sewage canal in to which i've seen people walking in sewage in the dart below razor wire, it would have been densely packed with individuals. but with individuals who by all accounts had a fairly slim chance of getting in. and there were still accounts people who went to that gate and tried and left later on in the day. it is unclear who the casualties are at this point. and one potentially saving grace for u.s. service men is that if that gate was not really functioning as much as i was led to believe it was, there may have been a minimal presence outside of the wire. i saw videos from yesterday which appears to show in a similar area some nato personnel outside of the wire. but things have been changing exceptionally quickly at this stage. so one point that your previous guest h.r. mcmaster was making to do with the insurgency. this is a complex series of extremists and while isis-k has been the terror group people pointing at for the last two or three days, they're also -- this sort after tac-- sort of attack from a group called haqqani's and they were into the taliban as part of changes they made for five years ago. so looking within the possible candidates if it terms to to have been a terror attack and that plaques that almost inevitable. there is not just one potential candidate here. and i should point out it does appear to some reporting that the elements of the haqqani network were provided the job of security around the airport as well. so this enormously fraught situation to some degree there were deep fears, we could have seen this before. but the crushing instead and the chaos seem to take over has potentially many different suspects. jim. >> no question. many groups capable. and the taliban, a group that carried out many hundreds of terror attacks in that country themselves, the targeted afghan civilians like this one appears to have targeted as well as u.s. forces here. as we said earlier, that the latest that the u.s. personnel are among those wounded among the casualties at the airport. the white house taking this seriously. we learned a short time ago that president biden has been briefed. our kaitlan collins at the white house. we're hearing the president is in the situation room on this. >> reporter: that is where he's monitoring all of the developments coming out of afghanistan including this explosion at the airport. as they are still trying to figure out what happened an the number of casualties. the pentagon has confirmed but trying to determine the actual number and what the except of the damage of this tack is. and so right now we are told by a white house official that president biden is monitoring this from the situation room with defense secretary lloyd austin and anthony blinken. they briefed the president at about 9:15 a.m. this morning on the latest situation in afghanistan and that is when we found out about the explosion that happened. so it appears he still is in the situation room monitoring there. whether or not we'll see from him at about 11:30 remains to be seen because that is when he's expected to be in the oval office with the new israeli prime minister. and there are a few other changes to the schedule this morning. because there was supposed to be a covid briefing up at 10:30 and they have now postponed that. just to give you a sense inside of the west wing. this is the number one focus right now. >> understood. understandably so. kaitlan, i know it is early, but any indication as to the president changing plans as a result of this or sticking to that august 31st deadline? he has been consistent on sticking to that deadline. >> i think that is the number one question for the white house right now is whether or not they are going to try to get these thousands of troops who are still on the ground out of there quicker than they had planned. because right now they were still working on evacuations. they were not prepared to get all of the thousands of troops out of there until closer to tuesday. that is something that the pentagon confirmed this morning. saying those evacuations were going to continue. but whether or not the security situation on the ground changes that dynamic, it remains to be seen because president biden is biggest fear was a threat like this, happening outside of the airport while there are still thousands of u.s. troops at that airport. >> and an attack like this, wounding u.s. service members which the pentagon is confirming to cnn that this attack has. gist into cnn, the first photographs of the scene following this bombing here. please take a moment here because i do want to warn you, they are disturbing. as you might expect. so take that moment and we're going to show some of them now. these are some of the casualties, civilian casualties it seems taken away in wheelbarrows from the site of this attack taken by eyewitnesses there. you could see the injuries. it also gives you a sense of where this attack took place. this is a corridor in leading into the airport. it is a very confined corridor and those kinds of corridors, number one, they put people in a very con fined space and makes for' very easy target for terrorists but too two it could also accentuate explosions because it is in a confined space. that is something that terrorists are aware of and take advantage of it. our nic robertson is with me now. we have covered our share of attacks like this one around the world. you and i were talking just yesterday about the danger and the level of concern among u.s. officials about an attack just like this one and it is now happened. and there are afghan casualties as we could see in those pictures there and tell us the significance of this. >> we knew the threat was there. we were told the threat was there and we've been told that the likelihood was that it would be a vehicle born explosive device and that is appears to be the indicators here and it's going to target u.s. forces at the gate. that was the expectation and the reason for targeting american forces was because the group want to create american casualties and they want to create you know fear and panic. this threat assess. that we've all been hearing in the past 24, 48 hours that have been growing, people were told to stay away from the airport and not go close to the gates was all around the threat that was posed by a vehicle born explosive device. and i think now for the president, for others in the situation room, the consideration will now have to go to what other threats could there be from the group. could they try to use gunfire for example to target aircraft taking off. we have no indication that they would intend to do that. but when you get into that discussion, you begin to say, okay, what caliber weapons do they have. do they have the light machine guns. yes. do they have heavy machine guns? yes. but what other tools do they have at their disposal and the concern will then become do they have the sort of personal packs, what are known as military jargon as man packs that they are launching that could launch a missile to hit an aircraft. now there is no indication and no evidence to support that they have that definitely, that they would intend to use it. and the threat assessment that was received was very clear. but these all become considerations and i think that has to be as this group has clearly demonstrates whom ever they are, we know that isis-k was believed to be the threat, and we know that they possessed good skills in suicide attacks so that is been their m.o. until now. but what else potentially do they have in their arsenal and of course that raises serious questions. >> well the thought occurred to me when i saw one of the flights take off in recent days and throw back the flares as planes do as a defense mechanism from any heat-seeking and it could be cautionary. but it occurs to me as i look at the photos of the afghans woundsed in this attack and to be clear we know that u.s. service members were also among the casualties in this attack. but when i look at the afghans i think of what they will be left to after u.s. forces leave here. the taliban running the country, the taliban a group that has cared out their own terror attacks targeting both civilians and u.s. service members. is this the future? that afghans have to look forward to? >> it is not a pret prospect in any way. if we just take the individual casualties on way to some kind of medical treatment, the taliban, we know that their lead leadership going to lead to a downturn there the kpi and that means every facet of live for after begans be it buying food and getting immediate cal treatment in hospitals where there is less material to repair them, that is all in the future. the potential for unpredictable attacks like this, this clearly remains. but the big thing on everyone's mind for particularly intellectuals and for human rights activists and for women and female journalists, particularly for anyone who doesn't hold to the taliban's strict interpretation of islam is a real concern about their rule. we learned last night from a source that even senior figures, former politicians, doctor abdullah abdullah, the former president hamid karzai who had until the past couple of days their own security detail and their own vehicles and now essentially holed up in a house without their transport and without any of their own security protection. many vulnerable, many afghans from top to bottom of society will be feeling exceptionally vulnerable, and that is fln indication of how the taliban