Nightly news begins now. Good evening. Brian is off tonight. Im lester holt. As we reach the oneweek mark in the search for that missing malaysian jet, experts agree that what we are witnessing is unprecedented in modern aviation history, a large airliner, packed with people, far from where it was supposed to be and then vanishing without a trace. Ing tonight there is new information showing the boeing 777 made not one, but two changes of course after it vanished from radar screens. And that has dramatically shifted the focus of search efforts while at the same time expanding the possibilities of where the plane ended up. So much about this flight simply doesnt add up. But that which does has investigators tonight accepting the real possibility that someone deliberately flew this plane into danger. Nbcs tom costello leads us off again tonight. Tom, i know they have been analyzing some data. What is it now telling us about the path of the jet . Reporter investigators are trying to determine if it headed north or south over the indian ocean. To do that, theyre using brandnew technology to trace an electronic ping off a satellite, similar to your cell phone pinging a tower even when youre not communicating. But that trace may only narrow the search zone to hundreds, perhaps thousands of miles. More than seven days as flight 370 disappeared, and still no firm sign of where the 777 with its passengers and crew might be. Malaysian authorities today laid out some of the possibilities. It could have been done intentionally. It could be done under duress. It could be done because of an explosion. So thats why i do not want to go to the realm of speculation. Reporter here is what investigators have. The military radar tapes showing the plane left its flight path, made a deliberate uturn and head west over the strait of malacca. The acars data, the planes automated data reporting system stopped transmitting data at 1 07 p. M. The pings. The plane did continue to send automated pings once an hour to an oshl orbiting satellite. They were received in london that said in a statement routine automated signals were received during its flight from kuala lumpur. Now investigators hope to use those pings to calculate where the plane might have flown in four to five hours. And hopefully with more work on the data and more refinement if you will, they can get a very good idea where the aircraft went. Reporter the new massive search zone now stretches from the strait of malacca to the bay of bengal where the u. S. Navy is searching. The uss kidd is now in the area as well. An antisubmarine plane loaded with underwater Search Technology should start working tomorrow. We talk to commander william marks. There is no way you can search the entire indian ocean. A ship is an amazing platform, but it cant be done with ships alone. And even our p3 and p 8 with a range of a thousand or so miles, theyll have to return. Reporter if they ever find the wreckage, the black boxes will be critical to uncovering what happened. The fdr should hold 24 hours of plane data. The flight data recorder will tell us hundreds if not thousands of parameters that are recorded on the airplane, what the airplane physically did. Reporter but the cockpit voice recorder only holds the last two hours, which means we may never know what happened in the cockpit that caused flight 370 to turn around. Investigators are also looking at what was in the cargo hold in the plane. Was there some explosive or flammable cargo on board. Theyre looking at this as well. Lester . Tom costello, thank you. And if you keep with the theory that it was a deliberate act, you have to assume everybody on the plane is under investigation, passengers and crew as authorities explore all possibilities trying to determine who might have had a motive and the ability to commandeer that plane. Nbcs keir simmons has more. Reporter as the search for flight 370 continues, malaysian officials are now looking at how the plane could have disappeared, and who might be involved, including the crew. The flights captain in his 50s, highly experienced. He had logged 18,000 flight hours. His copilot, farik hamid, 27, relatively new, with 2800 flight hours. Both are being investigated, but so is everyone on board. The key questions, who else on board could fly a 777 who might have a motive to commandeer the aircraft and for what purpose. And if the plane was hijacked, where was it going . During the crucial first hour of the flight, there would have been an opportunity to break into the cockpit despite security precautions. If there were to be a real takeover, that would be the time where the crewmembers would be moving in and out to serve the cockpit the drinks. Reporter there were prayers for flight 370 today at the copilots local mosque. Friends here call him a quiet, respectful man, living with his parents in this middle class home. Less is known about the pilots seen here at Home Improvement videos. He has a Flight Simulator at home. A man dedicated to flighting. But malaysian officials arent telling us much more than that. So the wait for answers continues. So painful for family and friends of those on board. Here at the airport they fill this wall with prayers and messages of hope for loved ones. They may never see again. Keir simmons, nbc news, kuala lumpur. We now want to bring in aviation expert greg feith, a Senior Safety director with the National Transportation safety board and a veteran pilot. Lets put to the side for a moment the question of who was flying the airplane. We heard in toms reports theyre looking at two possible course changes, one to the north and one to the south. If youre trying to escape detection, what is the more likely route . Lester, the more likely route is the southern route. Once you cross that little peninsula, now youre in open ocean. There is no radar coverage down there. It is a vast, vast ocean, going almost as far down as the south pole. And in fact we looked at this graphic down there. It points down off the coast at australia. Should they be searching in that part of the world now . Does the search area become that big . I think so. Theyre going to have to put assets down this since now they have a north track and a south track. And i would be looking primarily in the south track. In fact, with australia being down there, i may even request basically help from australia to assist in the search of that part of the ocean. You know, i said earlier today, weve gone past the farfetched point of this. Everything is kind of on the table. And we talked about whoever took it maybe wanted to land somewhere. If you took that southern route, there is no place to go. There is no place. It is open ocean. You can land it in the water. But if youre going that direction and your intent basically is to just do something bad to the aircraft, thats the place to do it because if that airplane even breaks up and sinks, thats a vast part of the ocean and the world. You may never, ever find the main wreckage. You may find some floating debris at some point, but that is the place to get rid of the airpt airplane. Cant recall a head scratcher like this one. Nope. An update on while we were on the air last night. An incident of a different nature. Officials say an accident on the runway at Philadelphia International airport happened when a tire, a front landing gear blew out on a us airways jet. It was headed from florida. It forced the pilot to abort takeoff. There were no reports of any serious injuries. The crippled plane was removed from the runway. Its now in a hangar where it will be examined by investigators. And in new york city Officials Say they have recovered all of the victims after that massive building explosion earlier this week. And all the miss having been accounted for. The final death toll stands at eight with some 60 people injured. A key turning point of the crisis in ukraine is coming this weekend. Voters head to the polls for a controversial referendum over crimea. But with diplomatic efforts stalled and Russian Troops firmly in control in crimea, some say the outcome is already decided. Nbcs chief Foreign CorrespondentRichard Engel managed to make his way to crimea. He joins us from there tonight. Richard, good evening. Reporter good evening, lester. In some ways, this referendum is a moot point. Russian forces already control crimea. They took it without a fight, and they wont give it up. For now, crimea is still part of ukraine. But these men have already sworn allegiance to russia. And today showed their strength under a statue of lenin in simferopol, crimeas biggest city. They are tough looking, ragtag bunch, armed with clubs and dressed in whatever they can get their hands on. These men and their russian backers now run things here. And many crimeans believe the upcoming referendum is just a rubber stamp for a takeover by force thats already happened. A takeover accomplished by thousands of Russian Troops controlling bases, airports, and other key facilities. And many crimeans are happy theyre here. Russia has Popular Support in crimea. Irena, a psychologist told us crimea was once the jewel of the soviet union. There are voices of dissent. But theyre faint. A few hundred today marched to keep crimea part of ukraine. But they held their demonstration by a roadside, run out of town by the pro russian militias. Do you think that crimea is now occupied by russia . Yeah. Obviously its occupation. Reporter but this isnt just about crimea anymore. Russia has mobilized 10,000 troops near ukraines border. Ukraine showed off its weapons too, but theyre no match for the Russian Forces many worry may be coming for Eastern Ukraine next. Already clashes have broken out there. Russias foreign minister told secretary of state kerry today his countrys troops will go no further into ukraine. But their faces show frustration and deep mistrust. Here in crimea, the facts are clear. The russian flag flies over parliament, the building under guard. President obama today again threatened sanctions. Diplomats tell us theyre not so much about trying to pry crimea away from russia. Even u. S. Officials acknowledge thats unlikely, but more about trying to deter russia from going any further. Lester . Richard, thank you. And an update now on our special series syria and the children of war. You might recall dr. Nancy snyderman told us about the premature twins born at a hospital along the syrialebanon border. One died at childbirth, and sadly, weve now learned that the second baby has also died, in part because of breathing complications. As for the 19monthold girl who doctors feared might have polio, theyre still waiting for final test results, but they say her paralysis could be the result of a small brain hemorrhage, and may be treatable. Theyre cautiously optimistic she will walk again. Still ahead tonight, historic freeze. The Amazing Mission to break the ice on the great lakes after the kind of winter not seen in decades. And later, theyre not done yet. Another big day for team usa in sochi. We probably dont need to remind you that its been a long and brutal winter, and all those storms and frigid temps didnt just make a mess of the countrys roads, rails and skies, its also snarled traffics on key rivers and lakes, including the great lakes. 92 of them were covered in ice, and clearing those shipping lanes is no easy tax. We get our report tonight from nbcs john yang. Reporter the first thing you notice is the sound. A constant deep rumble as the u. S. Coast guard cutter alder breaks up ice that has covered Lake Superior for months. Conditions are hard for the crew, single digit temperatures and winds topping 25 knots. And for the vessel. You hear the vessel shaking right snow . Bolts come loose, pipes freeze. Reporter off duluth, minnesota, the 295 foot alder pushes through ice as thick as four feet, freeing these one thousandfoot ore carriers, literally frozen in place. Without the icebreakers making the ports ready for commerce, it wouldnt move until the ice is essentially gone. Reporter the ships reinforced bow drives on to the ice, crushing it under the weight. This concrete block weighs 16,000 pounds. Its one of three on the deck here to give the alder extra weight as it breaks through ice up to several feet thick. Its among nine coast guard breakers on the great lakes turning plates of ice into smaller chunks that can be swept away by the wind. But the wind can also blow the ice back into shipping lanes and harbors. It just the force. Its a force of nature. Reporter the great lakes dominate the regions culture, economy, and climate. Theyll likely feel the effects of the ice well into summer. Its going to be i hate to say it, a lousy year for swimming here until about august. Reporter plus, water levels are projected to return to normal after recent record lows. But forecasters say it will be weeks before all this ice melts. Until then, the men and women of the alder will be outbreaking it up. The worst ice weve seen in about 25 years. Once in a generation kind of thing. Reporter a crucial mission for so many who live, work, and play on the great lakes. John yang, nbc news aboard the coast guard cutter on Lake Superior. Were back in a moment with the news today about an iconic american image. We learned today that Glenn Mcduffie has died. He was a navy veteran of world war ii and one of several men over several decades claimed he was the sailor seen kissing the nurse in the iconic life magazine photo taken in times square celebrating japans surrender. Mcduffies daughter said he only came forward after others claimed to be the sailor. He was changing trains in new york when he learned the war was over. He was so happy that he ran into the street and planted a kiss on a stranger. Glen mcduffie was 86 years old. And tough times continues for people in the food business. Quiznos says they have filed for bankruptcy to get out of 400 million in debt after losing ground to competitors like subway. The announcement comes days after pizza chain sbarro, a familiar sight in malls and airports filed for bankruptcy for the second time in three years. Paris is seeing some of its worst pollution in years, with the eiffel tower only visible through a thick blanket of smog today. Forecasters point to warmer weather, stagnant air, and a high number of diesel vehicles. The city of lights is encouraging people not to drive, instead offering free rides on transportation. Back on sochi, it was a good day for americans in the paralympics. The american men swept the snowboard cross, with 27yearold evan strong who we featured on this broadcast claiming the gold. It is the first gold for team usa at this paralympic games. Meanwhile, our hats are off to another competitor who we also kept our eye on, Tatyana Mcfadden won silver. In the 1 kilometerer sprint wednesday, proving its never too late. The wheelchair racer only took up Cross Country skiing about a year ago. And one last note, the the u. S. And russia hockey rivalry is renewed once again. The two mens teams will square off tomorrow for the gold medal. You can catch it at noon eastern time here on nbc. When we come back, a dream come true for one mother two decades in the making. Our final story tonight is about the incredible reunion of a mother and daughter who lost each other decades ago torn apart by war. Youre about to meet a pair of brave women who never lost hope. We want to thank our nbc station kusa in denver for bringing this remarkable story to our attention. We get our report from nbcs ann curry. Reporter amira ali is nervous, with tears and joy. About to meet a daughter she thought had died long ago. The dream is coming true. Reporter she last saw her little girl 24 years ago when their village was attacked one night in sudans brutal war. In the dark and the chaos, amira lost her 6yearold daughter tina. Believing tina was killed, amira fled with her other children, walking for days before joining the millions in refugee camps like the one we visited in 2006. What do you miss about being home . Reporter years later, amirrah made to it denver, starting a new life, studying english to become an american citizen. But she never stopped grieving for teen. That one day after a friend urged her to join facebook, the message that would be the shock of her life. I dont know what i do. I see her, i cant believe it. She came to me and said my daughter is alive. I found her through facebook. Reporter george brown is amirrahs english teacher. I just stopped and said wait a minute, wait a minute, lets back up. Reporter not only was tina alive, she was also moving to the u. S. Having just been granted asylum to escape the violence still raging at home. And it turned out that amiras sister, who amira also thought had died, had raised tina. Im so very, very happy. It is a long time to see my mom. Like i dream now when i see her, i cannot believe. But im happy. Reporter reunited with the daughter she thought had died, amira met a grandson she didnt know she had. God bless america. Reporter tonight in america, a family is singing. Im so glad jesesus loves me reporter knowing that even when all hope seems lost, joy can be found. Ann curry, nbc news. Thats our broadcast for this friday night. Thank you for being with us. Im lester holt in for brian. Ill see you later tonight for dateline, tomorrow morning on today, and then right back here tomorrow night. Have a good night, everyone. We still have faith and confidence that well get answerens and justice. The pather of a mi ee eer missing teenager shares hope, determination, and grief im jessica aguirre. Im raj mathai. Sierras body has never been found and her accused killer sits in jail awaiting his trial and her father continues his search. Marianne favro spoke to steve lamar today. Such a difficult journey. Whats the familys reaction at this point. Reporter he is frustrated by how long this case is taking to prosecute in the courts. He is also frustrate that despite hundreds of searches, two years later, he still has no answers. Two years ago this sunday, 15yearold syrierra lamar disappeared after leaving her home in morgan hills. She has never been found. Today her father talked to nbc bay area about the painful anniversary. Its even tougher, i think, these days just, you know, the frustration of it all and stuff, just kind