Let the speculation begin. The baby bomb may be making headline but theres more big news coming from hillary land. Good afternoon. Im jake tapper. The captain of a capsized ferry in south korea is in custody and has been criminally charged for the accident that has killed 29 people so far confirmed. 270 passengers, many of whom are High School Students, remain missing with the brutal likelihood that experts say its too late for rescue crews to reach them in time. The ferry is already completely submerged and though they were finally able to get on board, the rough waters quickly forced them out. Cnn has learned that the u. S. Is sending a salvage ship to the area to help pull the wreckage and presumably the bodies from the water. Families of the missing water, however, are not willing to give up hope. Rescuers managed to find air pockets. Even if thats the case, the maximum survival time at sea in 50degree temperatures was at around six hours. The ferry capsized more than 72 hours ago. With the effort hindered by choppy and murky water. The captain was not even in the steering room when the ferry sank. That is not surprising given that we know he was on a lifeboat 30 minutes after the accident. Many were told to stay where they were. Lets go live now to cnns kyung lah in jindo, south korea. Kyung, what charges does the captain face . Reporter hes facing a total of five criminal charges. They vary from negligence leading to death as far as abandoning the ship. He also faces a charge of causing Bodily Injury and not seeking rescue from nearby ships. This is something that the families who have been Holding Vigil at this port have wanted. They have wanted the captain to be arrested because they believe he was the one who issued the order. In speaking to reporters while handcuffed, he did admit that he was the one who issued the order telling passengers to stay where they are, to stay put as the ship was capsizing. He explained it as he was not sure where they would go, that there werent rescue ships nearby, that the water was too cold and the currents were too strong. But the fact that they were trapped as the boat was capsizing, according to these families, they believe that is criminal intent and this is a man who should be behind bars. So it will bring them a little bit of solace to hear that there has been some sort of prosecutorial step, jake, but its not helping them as far as what is happenings with their children at sea. Of course not. The images of the families at the banks is just heartbreaking. Kyung, some reports suggest that there are Cultural Values in south korea that may have played a role in why so many people remained below deck as the ship sank. Is there anything to that . Reporter certainly. When you talk about korean children, especially, and these are children that were talking about. These are High School Students who were not under the guardianship of their parents. They were a High School Field trip. What this culture prizes in its children and students is obedience. And so when they were told to stay put by an adult, of course they would stay put and so that is really what is infuriating a lot of the parents here. They feel that the adults should know better, that had their children been told to run to the deck that perhaps they could have jumped into the water, that they could have survived for a while longer before the rescue ships were there. So it is certainly heartbreaking for them because these are the very parents, jake, who have instilled that sense of obedience and listening to their elders. Absolutely tragic. Thank you so much, kyung lah in south korea, appreciate it. While we still dont know why it sunk, the time it took to go under could be telling. Tom foreman is here to explain. It only took about two hours. What are we to make of that . It does say that it was a catastrophic failure here. Think about what happened with this shape. Its sailing along and things are seemingly normal. There are various conflicting reports about whether or not people heard something. Nonetheless, the ship started listing, leaning to one side. Even though the captain spent half an hour trying to stop that, eventually it keeled and went down under the water. Thats why people think there may be air pockets because of the way it turned over. This ship is big. Its about 900 feet or 700 feet from one end to the other. It weighs about 7,000 tons. Let me show you the decks on this ship because theres five different decks ladened with different types of cargo and some of them passenger areas. We also know that a little more than a year ago, part of it was retrofitted and theres some question as to whether or not that changed the balance of the ship. Lets talk about that a little bit because this may be a critical thing to consider whether or not it hit anything that made it start leaning. When you talk about a ship, youve got to talk about the center of buoyancy, the part that keeps it up and then the center weight of the ship. You want to keep those basically balanced and one of the ways that you do that is by making sure that there is enough cargo positioned properly in the ship and that anything on board the ship is balanced in the proper way. If this becomes unbalanced and the cargo is suddenly way over to one side like this or you have perhaps water which is very common on Something Like a ferry like this slipping into one side of it, what it starts to do is create a very unbalanced weight situation and once you hit that, you can hit whats called the limit of stability on a ship like this and that limit is tipping and tipping more and tipping more and there is simply no way to retrieve it, jake. They will be looking at all of that. Tom foreman, thank you. Plenty of questions remain about why it took so long to evacuate the ferry and why passengers were ordered to stay put. Today the captain told the media, the tidal current was strong and water temperature was cold and there was no rescue boat and so i had everyone on standby and wait for the rescue boat to arrive. The man that led the rescue mission after the movie and the book the perfect storm. As soon as this happened, what should the captain have ordered the passengers to do, in your opinion . Well, as i understand it, within five minutes of whatever the event was, he issued a stress call. That indicates he knew he was in serious trouble. At that time he should have gotten all of the passengers up on deck, put them in life jackets and then started instructing them on how they would abandon ship, if necessary. They had the lifeboats and from some of the pictures that ive seen, i dont think even two lifeboats were used, if that many. There were many, many lifeboats unused. If they had instructed all of the passengers and had them up on deck and told them how they were going to abandon ship, should that become necessary, then the event would have turned out much differently. They should have a life jacket for every person and enough lifeboat capacity for every person. Its not like he would have asked them to jump into 50degree water and had there not been assets on scene, that would have been a bad idea. It would be difficult to recover them. But keep them on deck in their life jackets, instruct them on how to us auto the lifeboats and then when it became obvious that the ship was going to sink, then it would have been time to put in the lifeboats. If the captain got in a life boat and he got off, there was enough time to put people in the lifeboats. Thats why its so disenheartening the way that this was handled. Is it just Popular Culture that we are taught that captains are supposed to if not go down with the ship, at least be the last one to get off a sinking ship . Is that a real thing or is that just some nonsense we watched from the movie the titanic . Its the captains responsibility. The safety of the passengers is his responsibility and regardless of what the laws are, the requirements of his shipping company, everyone knows that the captain is responsible for what goes on with that ship. It was his responsibility to ensure the safety of his passengers. No, we dont want the captain going down with the ship. We dont want anyone going down with the ship but the captain should have been on the bridge and directing all of the operations and safely evacuated his passengers. Captain, were looking at a situation where its possible that hundreds of young people, children have died. It sounds like you think its possible that nobody had to die in this accident . Well, if they got one lifeboat off the ship, it would have seemed to me that they would have had time to put more people in lifeboats and get them off the ship and they would have had a better chance of surviving. Even if they were just up on deck in their life jackets they would have had a better chance of surviving. Once you put them down deep into the ship and tell them to stay there, as soon as that ship starts to roll over, its going to be extremely difficult for a trained professional crew member to find himself out of the dark and upside down and to get out. You cant expect that passengers are going to be able to evacuate the ship in that kind of manner. Based on what you know, though, i hate to be so stark and to put you on the spot, but based on what you know, did anyone have to die in this accident . I cant answer that with 100 accuracy or confidence. But i can tell you that theres no reason to have that many people trapped down below the ship whatsoever. No reason at all for that to happen. Captain larry brunicki, thank you so much. There were four transmitters on the plane that should have sent signals. Plus, the single deadliest incident on the tallest mountain. Why these guides risk their lives. Coming up. All stations come over to mission a for a final go. This is for real this time. Step seven point two one two. Verify and lock. Command is locked. Five seconds. Three, two, one. Standing by for capture. The most Innovative Software on the planet. Dragon is captured. Is connecting todays leading companies to places beyond it. Siemens. Answers. [ male announcer ] when fixed income experts. Work with equity experts. Who work with regional experts. Who work with Portfolio Management experts, thats when expertise happens. Mfs. Because there is no expertise without collaboration. music defiance is in our bones. Defiance never grows old. Citracal maximum. Calcium citrate plus d. Highly soluble, easily absorbed. Because you cant beat zero heartburn. Woo hoo [ male announcer ] prilosec otc is the number one doctor recommended frequent heartburn medicine for 8 straight years. One pill each morning. 24 hours. Zero heartburn. Welcome back to the lead. Im jake tapper. Now time for the world lead. Its been six weeks since 239 people disappeared on board flight 370. There have at times been irresponsible messages from malaysian officials, ones that have amplified the grief for the families. Were learning more about the boeing 777 and its flight path. The plane was equipped with four emergency locators designed to go off if it impacted with land or water. Its odd that it did not get picked up by the monitoring system. Flight 370 made that turn while in Vietnamese Air space and its altitude rose to 39,000 feet and stayed there for about 20 minutes as it flew over the malaysian peninsula. Our pamela brown has all of the latest developments for us. Reporter now under way, a sixth dive. This bluefin21 underwater vehicle is still the best hope for finding the missing plane. A fifth dive ended soon after it went into the water. A problem with the Navigation System had to be fixed before it could continue exploring the hostile ocean environment. Its extraordinarily difficult and then youre talking about an unchartered territory. Its like trying to look to see what is going on in the attic through the keyhole. Reporter more than 46 square miles have been searched. None of the sonar images from the bluefin has been released to the public. Its going to be a game of patience now and 15 square miles a day, every day we get a little more information back and we can write off the area that was searched. We dont have to go back to that. Its done. Reporter with the bluefin so far not finding any wreckage, the malaysian Prime Minister said that they are considering sending more vehicles to help in the search. Underwater searches can take a long time. It took vehicles similar to bluefin about 78 days over the course of two years to find the wreckage of air france 447 and that was after debris was found. With efforts focused underwater for flight 370, the search above the Ocean Surface is set to wrap up soon. Really its not that surprising that over such a vast area in such a long period of time that no debris has been found. Its disappointing for us, absolutely. Reporter in beijing, chinese families of the missing passengers gathered for a Prayer Service in a hotel after Chinese Police prevented them from entering a park. Family groups also published these documents pushing them to doublecheck the satellite data. Pamela brown, cnn, washington. Thanks, pamela. As you just heard, the malaysians have said theres a committee looking into whether to send more underwater drones to help in the search. Joining us is captain John Kazinski and van gurley is a former naval oceanographer and with metron service solutions. How quickly could these autonomous underwater vehicles move into the area and which ones should they be sending . Well, the first is, can they find something that is available . Its not like theres a warehouse with these things waiting for a call. They are fairly specialized pieces of gear and they are in use all the time. The equipment that the navy owns is what we call high demand and low density asset. First is finding something that you could use and second is nying flying it there so there could be weeks. In terms of the types, there are a number of other vehicles similar to bluefin21. One of the ones that im familiar with is the remus 6000. It was the type of vehicle that was used in the air france 447 search and it would be perfectly adapted for these areas. Theres other vehicles, too. Its sort of the production stuff. And then you get into the other technology that people have talked about. One are man submersibles. I would highly advise against that. It takes a lot of equipment for something that doesnt give you much bottom time and then you have towed sleds. There are pluses and minuses with those, too. I think if they are going to do it, they need to start doing it now because it is going to take weeks to get the equipment out there and to the search area. I want to ask you about the bluefin21 because weve been questioning all week whether or not this is the right device. Its the one they have and thats great. You mentioned others that are able to go deeper. Its exceeded its depth limit with some of these dives and people say there may be some residual risk to the vehicle because it is doing that. What does that mean . Would it make the bluefin21 inoperable . That depends. The pressure is building on you the whole time. You hear your ears pop when you dive into a swimming pool. Its 3 4 tons every 4500 meters. Every 100 meters in addition it goes down is an additional 150 pounds of pressure squeezing in. First, you could have one of the seals give way. Now you have water intruding into the Electronics Cabinet and its a catastrophic failure. Water and electronics is a bad combination. Dont want that to happen. The other thing is, they can get slightly out of alignment. And then the third is, you can have a catastrophic failure of the big steel pressure when its taken apart. Those at some point when you get deep enough will give way, too and then you have a vehicle that is lost. Sounds serious. John, lets talk about the flight path. Flight 370 made a left turn within the Vietnamese Air space. Is that significant . Should the vietnamese have some radar information . Possibly. Im surprised we havent heard more from them. If youre within 160, maybe even 200 miles from land, a civilian or possibly military radar should be able to pick you up at that range. If youre farther out than that, its not likely that the air Traffic Control radar will pick you up. But the difference between vietnamese and Malaysian Air space is more of an administrative line than it is a technical line in the sand. John, i want to ask you about the many being equipped with four emergency locator transmitters. They were not picked up. They were supposed to be picked up if they made contact with the land or water. Well, they are radio beacons that, given certain circumstances, are just like the pinger. They have a battery. They start transmitting a sound, a signal over a certain area just for beacons but normally they are designed to activate when there is a gforce. These elts are activated with a gforce. So if you lets say you ditched in the water just like the u. S. Air flight did in the hudson, youre not going to have enough gforces to activate the elts. If you hit the water really hard and the airplane sinks right away, then by the time those radio transmitters get underneath the water, the radio waves are not going to be able to propucgate. It subject sound like its that big of a development then. Thank you so much. The search continues underwater for the missing jet. That doesnt mean that they have not abandoned the search by air. One mission ended hours ago. Well tell you what they saw hours ago. Plus, what does Hillary Clinton need to win . Arianna huffington will join me. Stay with us. Scott appears busters been busy. Man yeah, scott. I was just about to use the uh. Scott thats a bunch of groundup paper, lad scotts ez seed uses the finest seed, fertilizer, and natural mulch that holds water so you can grow grass anywhere seed your lawn. Seed it hooking up the country whelping business run trains they haul everything, safely and on time. Tracks they connect the factories built along the lines. And that means jobs, lots of people, making lots and lots of things. Lets get your business rolling now, everybody sing. Norfolk southern whats your function . Helping this big country move ahead as one Norfolk Southern hows that function . Afghanistan, in 2009. Orbiting the moon in 1971. [ male announcer ] once its earned, usaa Auto Insurance is often handed down from generation to generation. Because it offers a superior level of protection. And because usaas commitment to serve current and former military members and their families is without equal. Begin your legacy. Get an Auto Insurance quote. Usaa. We know what it means to serve. Welcome back to the lead, im jake tapper. Continues with our world lead, the hunt for flight 370 is now focused three miles beneath the waves of the indian ocean but that does not mean that search planes have given up. Cnns own Miguel Marquez is joining us. Day in and day out, is there any sense of fatigue among the Aerial Search crews . Reporter there is fatigue but they are certainly not giving up. This is a p3 from the new Zealand Royal Air force that we have flown. The captain has flown some 30 flights. They are searching hundreds of miles from where the bluefin is diving. They have enough fuel for about an hour and and a half of searching and then its a fivehour flight home. Heres what the captain has said about the frustration. There must be a level of frustration at staring at the water for so long and hoping to see something and not coming up with it. Not so much frustration as in i guess its our mission to find it and we want to be the crew that does find it but it takes time. Reporter now, this prean las spotted a few things out there on the south indian ocean. They have been able to direct ships to them. So far they have not found anything substantial. The one thing that they did find that they thought they had a hit on turned out to be a large, red basket or bread holder. They thought they had something there. At the end of the day, it wasnt. It took hours to get the ship and there have been smaller boats to get to that piece in order to check it out. Its an unbelievable task that they have at hand. Jake . Miguel marquez, thank you so much. When we come back, what an agreement . He hasnt signed anything and his team isnt going anywhere. Will russia use their influence to convince them to leave those buildings . Plus, without them most climbers would not have a shot at climbing the mountain but without a dozen sherpas, will anything change . At t can help simplify how you manage it. So you can focus on what you love most. When everyone and everything works together, business just sings. If yand youre talking toevere rheuyour rheumatologistike me, about a biologic. This is humira. This is humira helping to relieve my pain. This is humira helping me lay the groundwork. This is humira helping to protect my joints from further damage. Doctors have been prescribing humira for ten years. Humira works by targeting and helping to block a specific source of inflammation that contributes to ra symptoms. Humira is proven to help relieve pain and stop further joint damage in many adults. Humira can lower your ability to fight infections, including tuberculosis. Serious, sometimes fatal events, such as infections, lymphoma, or other types of cancer, have happened. Blood, liver and nervous system problems, serious allergic reactions, and new or worsening Heart Failure have occurred. Before starting humira, your doctor should test you for tb. Ask your doctor if you live in or have been to a region where certain fungal infections are common. Tell your doctor if you have had tb, hepatitis b, are prone to infections, or have symptoms such as fever, fatigue, cough, or sores. You should not start humira if you have any kind of infection. Take the next step. Talk to your doctor. This is humira at work. Hooking up the country whelping business run build were investing big to keep our country in the lead. Load we keep moving to deliver what you need. And that means growth, lots of cargo going all around the globe. Cars and parts, fuel and steel, peas and rice, hey thats nice Norfolk Southern whats your function . Helping this big country move ahead as one Norfolk Southern hows that function . Crestor got more highrisk patients bad cholesterol to a goal of under 100. Way to go, crestor yeah getting to goal is a big deal, especially if you have high cholesterol plus any of these risk factors. Because you could be at increased risk for plaque buildup in your arteries over time. So, when diet and exercise arent enough to lower cholesterol, adding crestor can help. Go, crestor oh, yeah [ female announcer ] crestor is not right for everyone, like people with Liver Disease or women who are nursing, pregnant, or may become pregnant. Tell your doctor about other medicines youre taking. Call your doctor right away if you have muscle pain or weakness, feel unusually tired, have loss of appetite, upper belly pain, dark urine, or yellowing of skin or eyes. These could be signs of rare but serious side effects. Crestor yes [ female announcer ] ask your doctor about crestor. If you cant afford your medication, astrazeneca may be able to help. Welcome back to the lead. In world niece, you know the deal struck in geneva . The protestors say, hey, we never struck that deal. It was supposed to mean that the protesters would pull out and in exchange for a hold on more sanctions from the west against russia. Well, here we are 24 hours later and the protesters have not budged. In fact, the separatist leader in donetsk says they will not leave until the leader resigns. Meanwhile, troops are sitting on the other side of the border. They are not calming anybodys nerves. Senator bob corker of tennessee, the ranking senator on the Foreign Relations committee joins me from chattanooga. Throughout the crisis, it seems that russia has said one thing and done another. They said they were not trying to annex crimea and then they annexed crimea. They said they werent sending operatives into ukraine and of course we know how that has played out. Do you think the u. S. Is getting played here . Ive never seen a more confusing statement be issued where in essence everybody agrees to something and then people in ukraine are understanding it in a different way and obviously the actions on the ground, as youre mentioning, have nothing to do with what was agreed to yesterday. So look, i think the administration has created this air of permissiveness. What we did in syria by jumping into russias lap and letting them drive policy there after the chemical weapons issue came to the forefront is really been informative, i think, to the people of russia and i think they are in fact playing us instead of us moving ahead with sectoral sanctions which weve been urging them to do. Instead, we continue to watch what they are doing and try to respond to that. But it seems that in doing so we create a policy that is always a day late and a dollar short and dont have the desired outcome that wed like to see happen for our nation and our nations interest. I just have to ask, your leader, mitch mcconnell, the u. S. Should be providing lethal aid, arms to the ukrainians. Should we . I have to tell you, jake, you know, we signed the bucharist memorandum and said we would support their sovereignty when they gave up Nuclear Weapons in 1994. It seems that we are holding their coat while they are dealing with this issue and i think its time for us to consider antitank weaponry, antiaircraft weaponry. Obviously russia is going to far outman them. We understand that. But we need them to understand that they are going to pay a price if they do come in and its time for us to look at doing that. As a matter of fact, we are developing large wage on that front right now. Yes, i think its time for us to be doing that. Senator bob corker, thank you so much. Thank you. Also in world news, a tragedy near the top of the world. An avalanche on mt. Everest that killed 12 sherpas and four are still missing. The victims of the disaster, the native nepalese people that have been guiding people to the summit back up and back down alive. Everest, the name is synonymous with challenge and all too often with death. Todays avalanche is the single deadliest incident on everest in history. Despite the danger, the icy peak that rises more than 29,000 feet into the heavens still tan talizes those that come for different reasons. The sherpas take real risk for what are lucrative wages in nepal. Its not only the money that im after right now but even from my inner heart i always wanted to be on the top. The odyssey has been the subject of countless documentaries and featured filmed such as into thin air about the 1996 tragedy that left eight climbers dead. The dramatic scenes, perhaps, adding to the allure that has changed the dangerous mountain into a Tourist Destination but as the altitude increases, reality sets in. You can breathe for a while. Youre sort of losing ground as you do without oxygen. Reporter in 2012, american joe pratt struggled with the lack of oxygen at such a high he have lags, though he survived. Everyone who climbs mt. Everest and survives is lucky. 444 have been approved to climb this year guided by sherpas. Coming up, she says she still has not decided if shes going to run for president. Hillary clinton will talk about the hard choices that shes made. He was in charge of tracking down the suspects in the marathon bombing. I go back to the scene of the crime with the former Police Commissioner who shares some secrets and the manhunt coming up. Hey kevin. Still eating chalk for hearburn . Yea. Try alka seltzer fruit chews. They work fast on heart burn and taste awesome. These are good. Told ya im feeling better already. Alkaseltzer fruit chews. Enjoy the relief at your ford dealer think . They think about tires. And what theyve been through lately. Polar vortexes, road construction, and gaping potholes. So with all that behind you, you might want to make sure youre safe and in control. Ford technicians are ready to find the right tires for your vehicle. Get up to 120 in mailin rebates on four select tires when you use the Ford Service Credit card at the big tire event. See what the ford experts think about your tires. At your ford dealer. [ male announcer ] when fixed income experts. Work with equity experts. Who work with regional experts. Who work with Portfolio Management experts, thats when expertise happens. Mfs. Because there is no expertise without collaboration. [ female announcer ] most of the time its easy to know which option is better. Other times, not so much. So its good to know that Mazola Corn Oil has 4 times more cholesterol blocking plant sterols than olive oil. And a recent study found that it can help lower cholesterol 2 times more. Take care of those you love and cook deliciously. Mazola makes it better. Welcome back to the lead. The politics lead now. Former senator Hillary Clinton says my most exciting title yet, grandmothertobe. Bill and ir thrilled that chelsea and marc are expecting their first child. There may be little, subtle messages that were still sending to our girls and to ourselves that prevent us from pursing certain interests or jobs or opportunities. Clinton was speaking with her daughter at the clinton foundations no ceilings event. Whatever hillarys plans are for the future, she is not the only one pushing women to push themselves. And joining me now is ariana huffington, author of the book thrive. You have some competition coming out. We know that hillarys book is called hard choices and we have an image of what the cover of the book is going to look like. Weve been debating what that means, hard choices, the 3 00 in the morning phone call or personal circumstances shes had. Youre a wellknown progressive pundit. How do you see the title . How do you look at this . Well, maybe its kind of my hope but i wish that the title refers to the fact that remember when she left her job of secretary of state and they asked her what was she hoping to do next and she said the most important thing for her was to be untired. Do you remember that . And she paid her own price when she collapsed and ended up in the hospital, et cetera, et cetera. Im hoping that hard choices will mean making hard choices about how she prioritizes her own self, too, and how she deals with stress which, of course, could be incredibly rampant if she chooses to run for president. Shes about to be a grandmother. So i think she could be an amazing role model of someone who if she decides to run, even, would run and without completely burning out, as most of them do, and there are other ways to do it. You were talking about how she was going to deal and prioritize. One of the things that we know shes going to be prioritizing, shes going to be a grandmother. Chelsea clinton and her husband marc are expecting a child. A lot of pundits talk about what this means for 2016. I have a tough time imagining any potential male president ial candidate who is expecting a grandchild anyone talking about what it will mean for his 2016 race. What do you think . Well, jake, it could be worse. We could be asking ourselves whether they are yet to be born gra grandchild is going to be running for president in 2058 or not. At least we have not moved to that level of hypothetical speculation. Not yet. But the night is still young. So i want to talk about this book, the idea for it came from your own experience in 2007 when you write in the book right at the front, you were lying on the floor of your home office in a pool of blood and thats when you realized exhaustion was a problem for you and for this society. So what are we supposed to do about it . So we need to realize that we are living under a collective delusion that equates burnout with success and we have many role models that prove it but theres another way and why is it such an exciting time, jake, is that we have Scientific Evidence to show that you need to do whatever it takes to recharge ourselves and unplug from devices, were going to be more effective. Well, to be fair, you, arianna, are very successful and i have to say that your seven days a week culture of go, go, go is part of how you are so successful . Well, actually, ive looked back at my life and at many other peoples lives and i can say without any hesitation that i could have been just as successful without damage to my health and relationships if i had not fallen into this assumption. Arianna huffington, thank you so much. The book is thrive. Thank you so much. Coming up next, the bombing and the manhunt. A behindthescenes look at the Police Investigation that tracked down the tsarnaev brothers with the man in charge of it all, the former boston Police Commissioner telling me how they did it. Youre not going to want to miss this, coming up. Abe get in punch it let quicken loans help you save your money. With a mortgage thats engineered to amaze thanks, g. [ chainsaw buzzing ] humans. Sometimes, life trips us up. Sometimes, we trip ourselves up. And although the mistakes may seem to just keep coming at you, so do the solutions. Like multipolicy discounts from Liberty Mutual insurance. Save up to 10 just for combining your auto and home insurance. Call Liberty Mutual insurance at. To speak with an Insurance Expert and ask about all the personalized savings available for when you get married, move into a new house, or add a car to your policy. Personalized coverage and savings all the things humans need to make our world a little less imperfect. Call. And ask about all the ways you could save. Liberty Mutual Insurance responsibility. Whats your policy . Welcome back to the lead. For 26 years, all he ever wanted to do was to become a police officer. Sean collier was mere months away when one year ago today two men ambushed him on the m. I. T. Campus. They were the Boston Marathon bombing suspects. Today, boston, cambridge, a the m. I. T. Officers with whom sean served came together to honor his sacrifice. Sean was truly one of the brave ones. He made the ultimate sacrifice and he did it for us. Seans death was one of four in a weeklong nightmare that ensneared an entire community. We are going to take a look back. The new construction and welcoming storefronts cant make former Police Commissioner ed davis forget what happened here a year ago. As we trace the steps, he shares new details about what he calls an investigation on steroids. The first bomb detonated killing crystal campbell and wounding scores of other. The first bomb went off at the beginning of the construction site at the bay of that building. Reporter but it was the second site that proved most destructive, bringing the number of wounded into the hundreds and taking two more lives, Martin Richard and lindsey lu. They were still bringing victims from the scene when i arrived here. Reporter commissioner david got to work securing the area and anticipating another bomb at any moment. Al qaeda usually hits in three so we expected there to be a third device here. Reporter so you thought this was al qaeda . Sure. You have to think that as a possibility. These devices were clearly made by somebody who wanted to kill and maim a lot of people. Reporter investigators were forced to immediately pour over every potential clue. And there was no shortage. So were in this era where everybody has a camera. There are cameras all over the place. Did you suffer initially at least from too much information, too many photographs . Yeah, i think that was really an issue. They sent so much information in so quickly that our computers crashed. It was overwhelmed. Reporter but it was this camera that provided the critical identification of dzhokhar tsarnaev. They then traced his movements in reverse and found tamerlan. It was the events leading up to the blast and going back camera by camera, we were able to put them together. Suspect one and suspect two. Reporter once police releas released these images, they hoped that the public would identify him but just hours later m. I. T. Is reporting gunshots. Reporter the tsarnaev brothers allegedly killed sean collier and hijacked a vehicle to plan their escape. Around midnight the whole thing ripped open. The hijacking victim got to the phone and told us that he had been hijacked by two men that said that they were responsible for the bombing. We were able to track that car through a gps system and very quickly watertown came up with a vehicle. Reporter the Boston Police department is asking residents of watertown to stay indoors. The phone call that i got was commissioner, they are shooting at us and throwing bombs. So i was i was shocked. I had never heard that in american policing. Reporter in the chaos of the watertown shootout, brother tamerlan was shot by the police and ran over by dzhokhar escaping in a stolen vehicle. Tamerlan died. One of the officers was trying to handcuff tamerlan. I tried to pull him but i couldnt. Reporter dzhokhar was apprehended that night. The boston pd, the fbi, you all reconstructed the bombs that the tsarnaevs brought here. How complicated was that . They were complicated devices and the fact that these things went off in such close proximity showed significant planning. Reporter planning that the two brothers could not have done on their own, especially given their suspected ties to extremists. The fact that they were able to pull this conspiracy off and kill and hurt so many people, you have to look at that very closely. Theres a lot going on here and it needs to be fully vetted. Reporter this years marathon, this monday, will be strictly secured and debut a new rule. No backpacks allowed. How do you respond to critics who say, in a way, the terrorists are winning on that one . Theres no question, jake, that that will be an inconvenience to people. And people are upset about that. But the truth of the matter is, at this particular point, right now, with what we know about what happened last year and the state of the world, it just is a prudent thing to do. Well be going back to boston on monday for a much happier marathon day, a special live edition of the lead from boston. Tune in at 4 00 p. M. Eastern. Follow me on twitter jaketapper check for video blogs. Thats it for the lead ts q im jake tapper. I turn you over to wolf blitzer. Hes right next door in the situation room. Jake, thanks very much. Happenings now, sources reveal new details of flight 370 to cnn has the search continues, can these new clues with help to find the missing plane . Caught on camera, a ferry disaster as it unfolds. Do these images contain clues to the deadly