terrorists. isis releasing video today of what appears to be the gruesome execution of 31-year-old stephen sotloff. this is just 13 days after another american, james foley, was beheaded by the same terrorists. again today, we saw a masked executioner speaking in a british accent making a direct threat against the united states. jim sciutto begins our coverage tonight. >> reporter: the image is haunting and familiar. an american in an orange jumpsuit on his knees. his killer all in black standing above him brandishing a knife. 13 days after american james foley was killed, a new video appears to show journalist stephen sotloff brutally beheaded by isis as well. the masked executioner who seems to be speaking with the same voice and accent as foley's killer made it clear the murder was directed at the united states. >> just as your missiles will continue to strike our people, our knife will continue to strike the necks of your people. >> reporter: sotloff 31 grew up in south florida. he was freelancing for several publications including "time" and the christian science monitor when he disappeared while reporting from syria in august 2013. staring straight ahead his head shafben sotloff himself speaks to the camera before he was apparently killed. likely under duress saying he has to pay the price for u.s. intervention. next to him is another hostage identified by isis as david haynes, a british citizen who isis says may be its next victim. >> my son stephen is in your hands. >> reporter: only last week sotloff's mother released a video pleading for her son's life. >> i ask you to please release my child. >> reporter: today the president's point person on iraq brett mcguirk vowed a firm american response. >> this is just a reminder of the bar baism of this organization and i think president obama has shown that when organizations do these types of things to american citizens, they do not go unanswered. >> reporter: earlier today, the sotloff family released a statement in reaction to the video. it's a very short, it's a very sad statement. the family knows of the video and is grieving privately. erin? >> there have been two horrific beheading videos now in 13 days. do we know how many more americans are in the hands of isis who could be at risk of this? >> senior u.s. officials say that they know of a number of americans who are being held. they don't go any more specific than that in public, and the reason, frankly, is their safety and the sensitivity. they're not identifying them. they're not speaking to numbers because really any public statement could put them in more danger than they are, erin. hard to imagine that, but it could. their concern, of course, that they say something that might cause the terrorist to act or act sooner than they might otherwise. it's really dangerous, sensitive territory. that's why they tend to be very tight lipped in public. >> jim sciutto, thank you. >> thank you. >> joining me now is state department spokeswoman jen psaki. thank you for being with us tonight. >> my pleasure. >> did the united states know about sotloff's murder before the news became public today? >> erin, let me first say that our intel community is working as quickly as possible to authenticate the video. as we know, we unfortunately had to take similar steps a couple of weeks ago, but i don't want to get ahead of that process. obviously if this is authenticated, this brutality, this horrific act is something that certainly not only do our hearts go out to the sotloff family but raises the specter about the brutality of isil. beyond that i'm not in a position to get into additional details from here. >> a senior administration official tells cnn that it's believed isis is still holding -- and the words were, to be exact, quote, unquote, small number of american hostages. did the administration have a firm count on how many americans are there? >> we do. but for the safety and security of the individuals being held, we don't get more specific than saying a few. obviously we're turning any individual who is being held by isil or by any organization around the world is a top priority for the united states and something that we've been working on, unfortunately, long before the events of the last few weeks. >> so in terms of what might happen to those americans that you're talking about, people wonder exactly what happened with stephen sotloff and james foley who was horrifically murdered 13 days ago. we knew there was an attempt to rescue him and presumably sotloff in july. that video we saw where james foley was beheaded and stephen sotloff was standing nearby, was there another attempt made to rescue them? >> you're right there was the attempt early this summer. it's important to note that that wasn't our prechference for tha to be made public. there aren't additional details. of course there are efforts under way on a daily basis to do everything we can to bring americans home. we don't discuss those publicly because that could put the security and the safety of the individuals at risk and our efforts at rick. >> of course, the president being oversees got criticism from jane harman talking about his first remarks about this being in estonia. she says perhaps that was not the best decision. dianne feinstein has called the president too cautious on isis and adam schiff, a senior democratic on the house intelligence committee said that isis must be confronted and destroyed. is the president willing to go to war in the traditional sense, boots on the ground, american lives at risk, to destroy isis? >> the americans and the united states is not going to go it alone. no one in the american public wants us to do that. but there are a range of steps we've already started taking. the president has authorized 120 strikes in iraq. of course those have a range of purposes including providing humanitarian assistance and addressing those needs and protecting the american people who are there, but part of that impact has been on impacting isil and their growth there, but one of the main topics of discussion that the president will have, the secretary will have, secretary hagel will have will be about how the international community can address this threat. military approach is certainly part of that discussion. but so is financial efforts or diplomatic efforts or political efforts. we know this is an issue that can't be solved overnight and also can't be solved with just one component of a comprehensive strategy. >> you talk about the 120 strikes in iraq, then will the administration, will this president go ahead and strike in iraq as he's done in sear why. >> one, a decision hasn't been made in that regard but the president has been clear that he's not going to be limited by geography. and of course taking a look at what is most effective here, what is appropriate, what our options are is part of what he's doing right now. >> thank you very much jen psaki. >> my pleasure. >> rita katz is the first to obtain the video today. bob bayer is a former cnn reporter. how did your organization obtain the video? . hi, we have been researching the jihadist threat online for over a decade, following their steps, monitoring their activities and study their activities online any time lk already or isis become more and more sophisticated and that new technology, we follow that technology and we study their techniques. by doing that, we can predict where they might be uploading the videos online. after all, these videos are being disseminated online, they're published online, they have to go somewhere online for the des simmenation. we looked and found. >> you looked and you found it. you just heard the state department spokeswoman say they haven't authenticated the video. are you certain it is what it claims to be? >> the video shows the beheading of stephen sotloff. the location where the video was obtained from is the location that isis usually uploads their original videos to. the video shows a clear message from isis that follows the same message that it had before. and in fact, within a short time after our release, isis account on social media indicated that within short time they will be releasing the video, only we actually had that video beforehand and were able to beat them with the release. >> bob, when you see this video, are you surprised at all? did you think there was any possibility that this might have ended differently? obviously, we don't know when the video was shot, whether, obviously, 13 days ago there was another video, we don't know the time difference between each of these horrible beheadings, but do you thing the u.s. tried to rescue stephen sotloff between that and this one and failed, didn't try. what do you think happened? >> i think they would have rescued him if they could have, but it's a question of intelligence. he's probably being held in syria. it's very difficult for the united states to focus on that country, to get good intelligence sources. to get actionable intelligence, you really have to know where they are because otherwise you risk all their lives. they just didn't have the intelligence to go after them. and i think it was almost inevitable after foley that he would be next especially since we went on and attacked more targets inside iraq, and i think these people, we have to understand, is there without pity. i talked to somebody, a friend of mine who has negotiated with them. he said they're all europeans, the captors, in syria. they are, frankly, psychotics, and they probably take joy in murdering people and this is a tough group. and i think it's a lot tougher than al qaeda ever was. >> a lot tougher than al qaeda ever was. what is the threat, bob, they keep in these videos and we'll be going through it in the frame by frame reporter stuff in a moment, but what kind of risks -- do you take them seriously when they make these direct threats to the president of the united states, to the united states, that they want to take this to the u.s. homeland? do you take that seriously in intent and what about in terms of capability? >> i think the intent is almost certain, they would like to take the war to the united states. this group claims to be a state. it claims to be a cal iphate, ad like any war they take it where they can. they're certainly sympathizers and the question is capability. but what disturbs me is the longer american citizens are fighting in syria and iraq, the better they are at killing and when they come back, that's probably what they'll do. specifics on this, i don't have them but people that use tactical intelligence and deal with it every day say it's a very, very real threat. >> in terms the s ths of these you're looking at, do you have any sense of what they're doing next or whether they have these other americans that they say they have, what they plan for those from the sites you're monitoring? >> there is no information about other americans they have currently. we know now they have the next british guy that they'rethre threatening to execute. however monitoring the sites and seeing the celebration behind the release of these videos, the joy that they have when they see the beheadings of americans and how we terrorize the americans in other countries, there is absolutely no doubt that the recruitment aspect of these videos is something that we cannot ignore. there is a very important element to the recruitment in these videos maybe as equally as for the execution of attacks because we're talking about jihadi groups that don't -- that need the support. they need the general support. and the fact that they released the videos, both in english, by an executor who speaks english most likely with a british accent, gives the double message of this strong element for recruitment from isis. >> well, thanks very much to both of you, both roita and bob both using that horrible word "joy" when talking about the feelings about the beheadings. we'll go from the terrain to the mess anl of the executioner. family had kept secret for a year that he was being held captive holding out hope for his release. today they remember him. today a top official says the ebola outbreak is spiraling out of control. ugh. heartburn. did someone say burn? 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>> absolutely. two or three indicators there that suggest these two videos were not filmed at the same time. take a look at sotloff in first video 13 days ago, he appeared with a virtual shaved head. and also he didn't appear to have any growth or facial growth. in this video we've seen today he clearly has more hair and he also has evidence of stubble and a small beard. also in the video that we've seen today, there seems to be a lot of noise from the wind. in the video we saw two weeks ago very little wind noise. there's also another indicator and that the fact that the executioner refers to the u.s. air strikes on the town of amal-e in northeast iraq. that could put the time of stephen sotloff's execution some time after sunday into monday or tuesday. >> so it literally could have been done and then that video posted, which, if possible, makes it even more horrific and more chilling. karl, stay with us. i want to take a closer look at the two videos and see the other clues that they could hold with when and where they were filmed. what have you been able to learn from your analysis of the side by side here. >> these are tough, tough videos to watch. but here's a frame from the new video of the apparent murder of stephen sotloff and here is the killing of james foley over here. the terrain, the time of day, general appear eance are all similar. each of the victims is dressed in orange which isis uses to mirror the jumpsuits worn by prisoners at guantanamo bay. the executioner wears black keeping his face almost entirely cover. he holds a gun and he holds a medium sized knife in his left hand. he has the same general body build. gestures and demeanor in each one. so the question is, is this the same man? and that is important to analysts out there. >> it certainly is. i know that analysts say one of the clearest identifying characteristics on the tapes is the voice. as carl was talking about, the audio here. how does that sound side by side? >> listen to yourself, erin. if we listen to what's said by this man. listen in this video. >> you, obama, have yet again, for your actions, another american citizen. just as your missiles continue to strike our people, our knife will continue to strike the necks of your people. >> now, compare that to the voice and the murder of james foley. >> any attempt by you, obama, to deny the muslims their rights of living in safety under the islamic calf ittaiphate -- >> the accent in both cases sounds as if it comes from the london area. that suggests a possible link to dozens of radicals believed to have traveled from there to join the fight against the syrian government. people who are thought to be handling foreigners captured by isis. >> the intelligence community will go through every inch of this, every second analyzing the electronic impulses, the audio, the video, the speech, voice identification, the geography for whatever information it can provide as well as the production techniques and any embedded information that may be there. >> reporter: bottom line, erin, if they can go through all of that and somehow figure out who this person is, if it is the same person, that does give them clues into the power structure of isis and who's calling the shots from maneuvers like this one. >> tom, thank you. i want to bring karl penhaul back along with our counterterrorism analyst phil mudd. independent investigators at this point say they think they know where james foley's execution took place. that's the horrible video we saw 13 days ago in which stephen sotloff appeared. they say it's outside the town of raqaa, i could be saying it wrong, but es that outside the northern city of syria. do we think this was filmed in the same place? >> i suspect it was because my guess is the organization is trying to limit the footprint they show to anybody studying the video. they know western security services look at this. they know there might be identifying characteristics they can't fully understand but they believe we can exploit. my guess is they're trying to find as nondescript a place as we can, limit our exposure by hooding the person that's doing this, by creating a backdrop that's difficult to identify. let's do it in the same place so we don't give them too much to look at. >> if it's in the same place, what does that say about fact that no one in the united states or otherwise was able to, in 13 day, find that place and kill them? >> i don't think the place is particularly significant. let me tell you what i'd be asking if i were watching this at the bureau. two basic questions. the first question is, coupled with the decision the president has to make now pressured by the congress, about whether to strike in syria, do we have a good enough understanding of the intelligence architecture of isis to start destroying the element that's involved in bringing foreign fighters in, like this british kid who evidently did the murder of this journalist? it's not just can we strike isis locations. it's can we strike that sliver that's responsible for stuff like this. the second and final question if you're sitting in london, forget about who this guy is. when we get his name, what is the network that might have been involved in funding him, providing him documents, getting him in communication with isis? is there a residual network that's still recruiting kids like this. they've got to identify the people in the network because otherwise they might be recruiting other people today. >> ones who motivated inspired and made this happen. you've been running the videos past an acoustics analyst. >> that person's conclusion was that pretty much this does seem to be the same apparent executioner, the accent that he has is what our analyst describes as a british multicultural accent from the london area. what does multicultural accent mean? well, it means, yes, a london area accent but that quite probably this man grew up in one of the multicultural quarters of london where english is not always the first language, where there were other languages going around and other people would have grown up speaking other languages, hence the differentiation in tones the and accents as well. >> phil, what does this say about what they're going to do next or try to do next? we know there are few other americans being held. everything is being done that could possibly be done to try to make sure they don't face this same fate but there are only, apparently, from what we've told by the u.s. government, a small number of americans there. they're doing these videos to get attention, to scare people, to be vile, but what then? when they run out of people, what do they do? >> i don't think they're doing these videos to scare people. what they're doing by speaking to the president directly is to say, look, we're not just a terror group, we're a group that can have a dialogue with the united states, with the president of the united states, it will get global play. they're raising their game in a sense sort of like al qaeda did. you remember zawahiri didn't just talk about terrorism, they talked about global warming, trying to position themselves, believe it or not, as statesmen across this islamic world where they're trying to recruit people and raise money. they're trying to raise a profile to be viewed as people bigger than terrorists. i suspect there's a gap between the two killings because they wanted to get on tv when they kill this guy to say, look, it wasn't our fault. we gave the americans a chance. they continued bombing, and we had no choice. that time gap gave them in their eyes justification for the second killing. >> all right, well, thank you both very much. and a pretty crucial point that phil raises there about isis' desire to have a conversation with the united states. the question is whether the president has been too lax, too soft when it comes to dealing with isis. democratic congressman chris van holland is next. hackers break into accounts belonging to celebrities. the rich and famous are being exposed quite literally, what about everyone else? so factors like diet can negatively impact good bacteria? even if you're healthy and active. phillips digestive health support is a duo-probiotic that helps supplement good bacteria found in two parts of your digestive tract. i'm doubly impressed! phillips' digestive health. a daily probiotic. breaking news. another american apparently beheaded by isis. isis releasing a new video today showing the brutal execution of stephen sotloff who disappeared in syria last year. this comes just two weeks after another video showing the murder of american james foley. this time, isis has a direct warning to president obama. >> you, obama, have yet again. for your actions caused another american citizen gist as your missiles continue to strike our people, our knife will continue to strike the necks of your people. >> before his apparent beheading sotloff speaks to the camera saying he is, quote, paying the price for american military intervention. president obama is now aboard air force one. he's on his way to europe for meetings. jim acosta is "outfront" from the first stop of the president's trip, which is the capital of estonia, talinn. >> reporter: a white house official says he was briefed on this video before he departed on this trip for estonia. a senior administration official tells reporters that the intelligence community does not have any reason to doubt the authenticity of this video but they do want to go through the process of analyzing for answering key question, when was it shot, when was its recorded. was it the same person who killed american journalist james foley. at the same time this senior administration official said that the intelligence community still believes that a small number of americans are being held by isis so they're still in grave danger. all this comes as the president's policy on isis is coming under heavy criticism. he said last week he doesn't have a strategy for dealing with isis in syria. that prompted an avalanche of criticism. dianne feinstein wondered if the president was being too carb pou cautious. he'll have an opportunity to answer this. this trip was supposed to take place so the president could reassure countries like estonia that are part of nato that the united states and the rest of nato will come to their defense if they're attacked. people here in europe are very nervous about what's taking place in ukraine and they wonder if they're next. "outfront" tonight democratic congressman chris van holland. good to talk to you. 13 days ago a horrific beheading video. another one today. an american beheaded in syria. a noncombatant, a journalist. administration officials have said isis poses -- i'll quote him -- a very serious threat to the united states homeland, yet last week the president said, and i want to quote him, we don't have a strategy yet to deal with isis in syria. the question is, congressman, why in the world not? >> first, i think our prayers should all go out to the sotloff family tonight. second, the president has kept up the attack on isis positions in iraq. in fact, as you heard, some of the justification for this beheading was the fact that the president continued to provide air strikes in support of iraqi and kurdish troops in iraq. wr with respect to syria, the president is right that in order to accomplish the goal of eliminating isis, you need to have a concerted effort not just the united states being involved. it's very important that countries like saudi arabia, like turkey, sunni-led governments, are part of this effort. otherwise, you feed the isis narrative that somehow they're the rightful carriers of the banner of sunni islam. that would fuel their narrative. we need to put together a coalition that involves the sunni-led governments. by the way, as you know, helped create this frankenstein by looking the other way for many years. >> that's a fair point. the executioner in the video has a message directly to the president of the united states. he said i'm back, obama. i just want to play a small portion of that so you can actually hear his voice. >> because of your insistence in continuing your bombings despite our serious warnings, you, obama, have yet again for your actions caused another american citizen. just as your missiles continue to strike our people, our knife will continue to strike the necks of your people. >> congressman, you supported air strikes. there have been at least 120 in iraq so far, but why have there been none in syria where this beheading is believed to have happened. >> because the president and a broad array of national security experts have indicated, air strikes alone in syria are not going to do the job. so the first thing you want to do is actually stop the isis advance on the ground in iraq. we have done that, again supporting iraqi and kurdish forces. number two, you want a sustained effort against isis in syria, so we should be doing things like arming the kurds in syria. the kurds in syria were fighting isis there before we in the west were even talking about isis. we can be helping them. but in order to be effective in the long run, in order to accomplish the objective of getting rid of isis, you have to have these other sunni-led governments involved in the action because they've got to step up and say, isis does not speak for sunni islam, and if they're not part of it, you do feed the isis narrative that they're fighting the west. that actually draws more recruits, not less. >> what you're saying makes complete sense except for this. when you say air strikes aren't enough to do the job, as you just said, but then you talk about arming other people on the ground. isn't there perhaps a reality that it may take american boots on the ground, american weapons with americans holding them as opposed to arming other people, to stop a threat like this? is that a reality that we have to face? >> no, that would be a huge mistake. in iraq we've got the right strategy. you've got iraqi and kurdish forces on the ground supported by american air strikes to prevent the isis advance. again, american boots on the ground in syria would simply fan the flames of the sectarian banner that isis wants to claim it's carrying right now. this is why it is absolutely so important, erin, that the turks, who have been letting isis cross their border with impunity for a long time and the saudis who have been looking the other way while many people have been financing isis from saudi territories and other gouulf states, they need to get into this fight. if they're not in the fight, then isis is able to claim somehow that they're the twisted carriers of the sunni islam torch. that would simply feed their narrative, not defeat it. that's why it's so important to build a coalition for action. >> chris van hollen, thank you for your time tonight. >> thank you. "outfront" next, stephen sotloff, only 31 years old. he accomplished so much. i was looking at the video of him 13 days ago. i thought he was older than he was when you looked a his background and everything he accomplished. plus the cdc director's dire warning about the ebola outbreak. another american, the third, has tested positive for the virus. [ female announcer ] we help make secure financial tomorrows a reality for over 19 million people. [ alex ] transamerica helped provide a lifetime of retirement income. so i can focus on what matters most. [ female announcer ] everyone has a moment when tomorrow becomes real. transamerica. abe! [ female announcer ] everyone has a moment when tomorrow becomes real. get in! punch it! let quicken loans help you save your money. with a mortgage that's engineered to amaze! whenwork with equity experts who work with regional experts who work with portfolio management experts that's when expertise happens. mfs. because there is no expertise without collaboration. veggies you're cool... reworking the menu. mayo, corn dogs...you are so out of here! ahh... the complete balanced nutrition of great tasting ensure. 24 vitamins and minerals. 9 grams of protein... with 30% less sugars than before. ensure, your #1 dr. recommended brand now introduces ensure active. muscle health. clear protein drink and high protein. targeted nutrition to feed your active life. ensure. take life in. the breaking news tonight. video released by isis appears to show the beheading of a second american, a journalist, 31-year-old stephen sotloff. so who was he? why was he there? cnn's alina machado joins us to talk about the sotloff family's ordeal. >> reporter: few knew he was being held captive by isis for the past year until two weeks ago when this video surfaced. even when isis threatened to execute sotloff after james foley, his family and closest friends held out hope they'd see him again. his mother issued an emotional plea last week. >> as a mother i ask your justice to be merciful. >> reporter: the family's home has now turned into grief after a video released by isis today appears to show the 31-year-old's gruesome killing. sotloff grew up in south florida but went to high school in new hampshire where he played on the varsity football and rugby teams and appeared in the musical "cabaret." the school issued a statement saying in part, his courageous actions have and will always inspire our students and our community. emers emerson, sotloff's roommate, was too distraught to talk on camera, but tweeted, devastated and crushed. steve was an amazing friend. heart is heavy for his family. while at ucf sotloff talked about wanting to go to the middle east, he eventually did freelance work for several publications including "time" magazine, foreign policy and the christian science monitor. he was on assignment last august when he was kidnapped. the family remains tight lipped despite the growing media presence outside their home here in pinecrest, florida. they did release a statement, though, saying in part, they are aware of the video and they are grieving privately. erin? >> alina, thank you very much. as alina said, we understand the family has said they are grieving privately. they also said they're awaiting confirmation that this is indeed the video of their son. as we have reported, the united states government has not yet formally confirmed that this was stephen sotloff in the video. next "outfront," another american doctor infected with ebola. health officials warning the outbreak is going to get much worse. plus the feds now investigating how nude photos of famous female celebrities the were leaked. did hackers actually catch apple, which you probably, you know, store your stuff in the cloud with apple, right? could it be you next? we are a collection of smalls. a home saved. a hero homebound for a new opportunity. a kitchen that kick starts careers wells fargo invests in our communities a little differently. small measures that add up to make our whole even greater. little by little we can do a lot. because... small is huge. visit www.wellsfargo.com to see how big small can be. another american with ebola, an american missionary tested positive. we don't yet know the doctors name but it was said the ebola outbreak is spiraling out of control. he briefed president obama on the crisis as tests began on an experimental vaccine and joining me is dr. anthony overseeing the first human trials of the vaccine. dr. fouche, thank you for being with us. >> it's the first in a multi-step process to get a vaccine out as quickly as possible to prevent infection. this is a vaccine that did well in animal studies in a monkey studies, in which it protected animals that were challenged with lethal doses of ebola. having gotten that out of the way where it looks good in the animal, the next step is to see is it safe in humans, do you not get any unexpected type of adverse events and does it induce the response that you would hope it would in the human comparable to the animal and we started that in the first patient today here in maryland. we did the first injection of a normal volunteer with this vaccine, first time in a human. >> and so, what can you tell us so far in terms of how that worked? and again, the human, that person obviously doesn't have ebola, right? so how are you going to be able to tell if it works and what are you able to tell in the past few hours since you gave the injection? >> the development of a vaccine is a multi-step process. before you think about if it works since you give it to normal people, you have to determine right from the beginning a, is it safe and what is the right dose of its safety? so the significance of this right now, we'll have about 20 normal volunteers, and you always pick normal people because you don't want to confound the question of do they get an adverse event with some under lying disease they have. >> right, right. >> you do that for -- yeah, so what you do is you do that for a period of a few months to observe them and then if it looks safe and looks like it's inducing the right response, you go into a broader study to determine if it works. >> right, two former bush administration health officials wrote today and i'm sure you saw it but their point is the longer this outbreak lasts, the more chance the virus can develop random muni titationmutations. is that a big risk? >> that's not a big risk, erin. that's a risk but it's unlikely to see that happen unless this goes on for a very, very long period of time. so the mutations you see, which are considerable, most of them are irrelevant. most of the mutations that occur, once in awhile you get one buy logically insignificant. to shut this down now, it's not going to be a vaccine not ready for awhile. it's not going to be a drug. it's going to be the good health practices of isolation, identification and contact tracing, which we need to intensify right now. >> thank you so much for your time tonight. >> good to be with you. next, hackers leak nude photos of jennifer lawrence and other celebritiecelebrities. could you be next? save you fir more on car insurance. everybody knows that. well, did you know the great wall of china wasn't always so great? hmmm...what should we do? geico. fifteen minutes could save you fifteen percent or more on car insurance. so factors like diet can negatively impact good bacteria? even if you're healthy and active. phillips digestive health support is a duo-probiotic that helps supplement good bacteria found in two parts of your digestive tract. i'm doubly impressed! phillips' digestive health. a daily probiotic. it's a place you've been before, but it's not on any map. so go out there, lose yourself, and find the truth. ♪ we're all born wild. ♪ let's keep it that way. the 2014 4runner. toyota. let's go places. the fbi is investigating how nude photos of actresses like jennifer lawrence ended up online for the world to stare out. many have been stored on apple's i cloud storage system, which you probably use. how did it happen and could it happen to you? is dan simon. >> reporter: jennifer lawrence and other's photos splashed on the internet. they have claimed to have targeted more than 100 celebr y celebriti celebrities. apple's i cloud emerged as a likely target. one tweeting thank you, i cloud. we discovered certain celebrity accounts were compromised by a cyber attack on user names, passwords and security questions, a practice too common on the internet but the actual systems were not breached the company says. this raising concerns about the security of the cloud. most of us rely on it, whether we most photos to facebook, use a service like drop box or have contacts or e-mails stored with google, apple or any number of internet based services. >> the cloud like any other piece of technology has positives and negatives. >> reporter: he's the chief technology officer for lookout mobile security, a big player. >> the positives are if you store your data in the cloud, it's less likely to get lost. if you lose your phone or your phone breaks or drop it in the lake, you usually lose your data. the cloud protects you from that but ex many poses the data to breach. >> reporter: sometimes, if you delete a photo from a device, it may still live on the cloud. still, experts say the two main ways to better protect your data are first, by creating strong and unique passwords and second, enabling two-step verification where you have to enter a four or five digit code sent by text. do you have a sense if this was professional or armature? >> my speculation is probably more armature side. professional hackers tend to go after critical things like oil and gas, nuclear power plants or other espionage where armature hackers might do it for fun to cause chaos. >> reporter: for the stolen photos, the fbi is actively investigating the breach. some victims like jennifer lawrence said the photos were real. others say they were fake. erin? >> wonder who to believe? >> wonder who to believe? thanks very much. -- captions by vitac -- www.vitac.com good evening. thanks for joining us at the end of a brutal day that may not be over. isis put out a video of a murder of a captive. american president on root to perhaps the most important global moment of his presidency, challenged directly and personally challenged by a knife-welding thug. just as in the killing of jim foely shows a masked man carrying out a ritual in the name of god. i'm back obama