Tonight. The images from belgium to america, lit up in their honor. From abc news, this is a special edition of world news tonight with david muir brussels under attack. Welcome back to our special edition of world news tonight of the terror attacks in brussels, and tonight, the casualties y s ies mounting, after terror attacks at the airport and in a subway car. Long. Blitz police with weapons drawn. An explosion on a subway car during the morning rush hour. A scene of chaos, right there in the dark. Abcs Alex Marquardt in brussels this evening, taking us through the attacks, and the new focus at this hour on the Surveillance Video now. Under siege. An allout search for the man in seen walking through belgiums main airport. The two men in black believed to be his acome polices. The attackers hitting at the height of rush hour. Around 8 00 am, two blasts. Suicide bombers in the departure hall outside the security checkpoint. The terminal filled with smoke and the sound of screams. Travelers lying top of each other on the floor. This man holding a little girl. Stay down. Stay down. Reporter the bombs so powerful that ceilings collapsed. The wounded treated amid the you have to go outside. Reporter outside, smoke pouring out of shattered windows as people raced away. It exploded behind us. If we were at the at the checkin, we exploded, too. Reporter at least ten dead here, at more than 100 injured, including nine americans, mormon missionaries richard norby, joseph empey and mason wells from utah, and an american air traveling back home with his family. But the horror was still unfolding. 9 11 am, just an hour after the airport explosion, seven miles away another suicide bomb goes off near the offices of the european union. This time in a packed metro car, as it was leaving the station. In the dark tunnel, passengers climbed out of train cars. The terrified screams of a child. The path to safety down the dimlylit tracks. At least 21 people dead. More than 100 wounded here, too. And at 4 19 p. M. , eight hours after the terror began, isis claimed responsibility. Brussels tonight , a city gripped by fear and uncertainty. And Alex Marquardt with us live again this half hour from brussels. Alex, you told us at 6 30, the city largely shut down tonight. What do we know about the subway systems there, and the airport, of course, which has been locked down today for quite some time. Authorities are trying as hard Transportation System back up and running. The metro system tonight still shut down. The airport tomorrow will still be shut down. Brussels. Parents keeping their kids at david . Alex maher quart, thank you. As we reported earlier, the terror attacks in brussels may have been triggered by the capture of the most wanted man in europe. We showed you heavilyarmed Police Nabbing the final suspect in the paris terror attacks, wounding him in the raid, and then interrogating him. Abcs chief Foreign Correspondent terry moran showing us this half hour how city. He was able to get right to the center of brussels. He is back with us live tonight. Terry, this has been one of the chief criticisms there, that its very easy to get in that city and in and out of that country. Reporter it is easy to get around this city, even given these attacks today, and getting in and out of this country, into europe, without borders, is also very, very easy. Terrorists. There are so many safehouses and depots and networks that hid salah abdeslam, who was arrested last friday, for four months, right undernoses of belgian authorities. It shows how far behind authorities are. Theyre trying to crack down, but right here, people have a much more urgent question, given the weakness of the government whats coming david . All right, terry moran with us live from belgium tonight. Terry, thank you. And among the survivors i spoke with today, a pregnant woman in the airport. Her husband lying on top of her, moments after the explosions. I spoke with her a short time ago. We heard an explosion, and we thought something was going on and the debris started falling on us. Pieces of the ceiling were falling down on you . Yeah, i mean, the debris was falling on us from the roof, we thought the roof was going to collapse. Youre pregnant. And it was your husbands instinct to try to protect you from the falling debris . Yeah, so, he immediately ran to me and he grabbed me and he kind of tried to cover me, because in his head, we discussed later, he thought that theres probably still gunmen around. Can you describe for me the scene inside for the other passengers who were there . How terrifying this was . Yeah, im im i was very, very shocked, because in a really strange way, i was extremely calm and alert, and, like, it was an out of body experience, because everybody was running in different directions, each single person, running in different directions, sobbing. Were really glad that youre okay and that that baby is okay. Thank you so much. It is really a relief, and our heart really goes out to all the other people who have been injured, even slightly. Sneha talking with us just a short time ago, early in her pregnancy. She and her husband, okay tonight. Americans injured in the attacks in brussels. Three mormon missionaries with from utah among them. Tonight, all three are at hospitals. One of them, already surviving a close call at another terror attack, the boston bombings. Abcs Clayton Sandell now with the americans injured in belgium. Reporter those three mormon missionaries seriously hurt in the blast, richard norby, joseph empey and mason wells, are from utah. They were at the airport this morning to see off a fellow missionary, also injured, 20yearold fanny clain of france. Wells is 19. He was burned and hit by shrapnel, but able to call his parents today from his hospital bed. But your eyes are okay . Yeah, and my right hand is also kind of badly burned. He was extremely close toe the blast. Words cant describe the joy and the relief that we felt to hear his voice. Reporter empey is 20. His injuries include second and third debris burns. Church in utah. Remarkably, this is the third terror attack for mason wells. He was only a block away from the Boston Marathon bombing. Wells was also in france last november when terrorists attacked paris. I just have to think that he was prepared in some way to go through this. Reporter and david, all nine injured americans are expected to survive. The u. S. State Department Says so far, they dont believe any americans have been killed, but they are still trying to account for all u. S. Citizens and government employees. David . Clayton sandell with us this half hour. Clayton, thank you. And next, to the high anxiety here at home and a more visible show of force tonight. In times square here in new york city, Armed Police Officers standing guard at this hour. Abcs chief justice correspondent Pierre Thomas now on the lone wolves. We asked the fbi, how many of them are being monitored right now here in the u. S. . Reporter right now, the fbi continues surveillance on tozens of isis sympathizers thought most likely to act out on short control from the group, most targeting isis supporters radicalized online through social media. For those suspects receiving most scrutiny, 24hour surveillance, often requiring dozens of agents. They may shake the bushes, so to speak, to make sure that they know that they are being watched. Reporter and while officials in the u. S. Dont believe there are sophisticated terror cells like those in europe, in the past two years alone, at least 103 americans have been charged with trying to join isis or suspected of supporting the group in some way. Of those identified, 82 are men, 16 women, half, 52 suspects, are ages 18 to 25. Ten teenagers. Just recently in San Bernardino, that killer couple allegedly swore allegiance to isis before gunning down 14 people. Authorities worst fear . The couple was hiding in plain sight. As one of the killers coworkers told our david muir. If somebody asked you before yesterday, if he was a friend i believe so. Law enforcement officials are pouring over the recent intelligence, looking for any sign of a threat here at home. And in some cases, some of the suspects of the fbis radar may have agents knocking on their doors to warn them theyre being watched. David . Pierre thomas live in washington tonight. Pierre, thank you. Want i want to bring in matt olsen, live with us tonight. And you heard what pierre reported right there. For 24hour survey illance only some of some of the suspects theyre watching around the united states. It could take perhaps dozens of agents. It almost sounds overwhelms. Well, it is. What we dont have here is the same problem they have in europe. They have thousands of foreign fighters who have gone to syria and returned to those countries, which really is overwhelming for the Security Services in places like brussels and paris. So, what do you do, matt, in the meantime, if you cant have 24hour surveillance, which we all know is the reality here, how do you keep these attacks from happening . Believe, were right there in the neighborhoods who had been searched in belgium. You know, the key, david, is good intelligence. You need to have surveillance, informants. The best way to stop an attack like this is to know about it before it happens. Its very difficult to protect vulnerable targets like a train station. Just difficult pictures to look at there from the subway, too, today. Matt, thank you. As we continue with these bombings at the brussels at home. At the Orlando Airport today, bruceles. It was met by police cars. Everybody going through an extra security check, because of where that jet was coming from. But todays bombings taking place outside the secure area, where families were leaving off their loved ones and saying goodbye. They were simply lining up for their tickets, so, Abcs David Kerley on what, if anything, can be done here. Reporter tonight, part of a terminal at denver evacuated, a security scare. In orlando, that jet from all this, the anxiety after the on motorcycles, armed patrol and fourlegged bomb sniffers. Responded to the brussels attacks. But the bombings in a terminal, just like these, are leaving some travelers worried. We had a little bit of today. Its scary. Its very scary. Reporter with the airport shut down, the airspace over brussels cleared, as jets canceled. Unsecured area, always has been, right . Completely unsecured. Reporter before the security checkpoints here in the u. S. , term thats are considered soft targets, with only some police presence. So, is this a risk we have to live with . Clearly entered a period of new normal, where we have to be concerned about a much broader range of attacks. Reporter Homeland Security announced today tsa will tightening sturt, but tsa is now responsible for the overall security at airports, just these interestingly, the head of tsa was actually landing in brussels around the time of the explosions this morning, david. He was taken to a secure area. Thats just incredible. And of course the larger question looming is what can you do at ticket counters . You cant secure everything at the airport. David, thank you for that report tonight. And isis taking responsibility for the terror attacks today, as the military battle against isis rages on. U. S. And Coalition Forces taking on the Islamic State at its roots. American fighter jets taking off around the clock, targeting sites in four countries now. Abcs chief global ail ffairs correspondent Martha Raddatz just back from the region, and she shows us tonight what she saw firsthand. Reporter the air strikes have been constant. From the sea, from the land. Were out here to take out isis so it doesnt matter where theyre at. Were going to eliminate that threat. Reporter Surveillance Drones and cold war era spy planes patrolling the skies to help locate targets. The ground war, too, has been isis losing 40 of its territory, says the pentagon, but there are estimates that 3,000 isis fighters are still spread throughout the region. We tracked one Night Mission from start to finish aboard the uss truman. F18s flying over syria to destroy an oil pipeline, a Revenue Source for isis. Three, two, one. Reporter we met with the pilots on the flight line seconds after returning safely to the deck. It was not exactly routine. But we got the results we wanted. Reporter the u. S. Says intelligence has improved in the million tear fight, especially with more u. S. Troops backing up iraqi troops. And, david, while the pentagon says that isis is weaker and on the defensive, the pentagon is the first to say that defeating isis will take more than military might. David . Martha raddatz, thank you. And there is still much more ahead on this special hourlong edition of world news tonight. Brussels today, the terror investigation here at home, after San Bernardino. How did the terror suspects plan their attack overseas, and how did they communicate right here at home . There are new developments tonight involving the iphone at the center of the investigation here in this country. As our coverage of brussels under attack continues in a moment. The roles you play in life are part of what make you, you. And youre not going to let anything keep you sidelined. Thats why you drink ensure with nutritious calories, 9 grams of protein and 26 vitamins and minerals. Come on, grandma giving you the strength and energy to get back to doing what you love. From the 1 doctor recommended brand. Next tonight here, as america honors the victims of those attacks in belgium today, here at home, there are new developments tonight after the terror attack here in the united states, in San Bernardino. The fbi now saying it may not need apples help after all to unlock that encrypted iphone belonging to one of the shooters. Abcs Neal Karlinsky on if the fbi will break into that phone. And the bigger issue, how do you cover the conversations of these terrorists before the attacks . Reporter tonight, the hunt is on to dissect every moment of these three possible terror suspects lives. A search that will run straight Law Enforcement struggles to uncover their digital footprints. Investigators faced the same challenge last year in paris. There, uncovering a huge stash of disposable cell phones. Many activated only one day before the attacks. And back here in the u. S. , investigators continue to struggle to unravel the iphone used by San Bernardino shooter syed farook. Tonight, in a bold aboutface, the Justice Department now says it may not need apple after all, putting the brakes on its Landmark Court bat until the 11th hour, and telling the judge, an outside party demonstrated to the fbi this past weekend a possible method for unlocking the phone. Apple has fought the governments attempts to force it to weaken iphone security so investigators can break in. We have a responsibility to help you protect your data and protect your privacy. Reporter but its not just apple. Third Party Messaging Apps used by terrorists, and Law Enforcement worldwide is just struggling to keep pace. David . Neal karlinsky tonight, thank you. When we come back, the race for the white house here, and the voting under way at this hour. Fighting terror, a top priority in the race for president , as we all know, as voters now cast ballots in three states tonight. Donald trump, Hillary Clinton, the front runners. And later, whats being done at the eiffel tower and at ground zero here in new york, as we honor the victims in belgium. Edict. The market. But at t. Rowe price, we can help guide your investments through good times and bad. For over 75 years, our clients have relied on us to bring our best thinking to their investments so in a variety of market conditions. You can feel confident. In our experience. Call a t. Rowe price retirement specialist or your advisor. To see how we can help make the most of your retirement savings. T. Rowe price. We should note tonight that voters in three states are going to the polls. Republicans and democrats weighing in in those three states. Utah, idaho and, of course, donald trump and Hillary Clinton clashing over how to keep america safe today, trump calling for using methods that go beyond waterboarding. Clinton saying torture does not work. Senator ted cruz with his own solution, patrols of muslim neighborhoods here in the u. S. Senator Bernie Sanders calling that not only wrong, but they are also voting in arizona. When we come back here on a tuesday night, the tributes in light. The incredible images coming in at this hour, as the world sends finally tonight here, on this hourlong edition of world news tonight, the global show of solidarity in the wake of the bruce ms attacks. The World Trade Center lit up tonight, and the simple words going viral across the world. Heres abcs david wright. Eiffel tower in paris, at the brandenburg gait in berlin and the trev i have found tain in rome, black, yellow and red. Solidarity from cities that have been there, saying, sadly, welcome to the club. A club with too many members. Tonight, people are making room at vigils and memorials worldwide. Belgiums most famous cartoon character, tin tin, and snowy, tonight, in tears. The caption says belgium weeps for her children. Terror is not the only result of violence such as this. Theres togetherness, too. Strangers united. Comforting each other. Deploring an act of hate. Now at 730. Miles from terror. Uc students studying abroad in belgium are safe tonight. Following several deadly blasts. What comes next for the group as the country remains on high alert. Plus the Vice President stops in the queen city with a message for ohio voters. What those inside the private event are saying about his quick visit. And a brawl breaks out at a