. >> tom costelo let's bring in daniel rose. what do you have -- what is your thinking when you listen to tom's report there? where are you at when thinking of what happened here? >> i think tom brings up very good points about the wreckage field if it ends up being the debris field being a very strong fact in this investigation. if nothing else it tells us tragically that there likely weren't survivors. it is still a big if. we have been inundated with facts for over two weeks now and almost three weeks where some have proven to be inaccurate and have been looking at satellite images for the better part of two weeks now that really haven't come to fruition in terms of validating that is actually the aircraft wreckage. once we have that and hopefully we will soon we still need to go back and back track to figure out where that aircraft impacted the water because that debris field if that is what it is floated and moved a great distance in the last two weeks. we have a lot of work ahead of us. >> philip woods mother gave a rather

costelo is ceo deck in china. he wants to get twitter into china but the characters are different.ny likelihood that twitter will be unblocked in china? >> it's possible but it's very difficult for what a western company to be able to work into the chinese media. that's because there are so many different types of relationships with the government in different agencies at all levels. >> twitter has said this is a her small visit to speak with universities and he is trying to find out more about what they are thinking and how they work. i want you to describe the differences in the services and the competition between weibo and wechat which is owned by 10 cent and how many people actually use twitter. talk to us about that landscape. there were some features of weibo that predated twitter and twitter adopted. >> absolutely, the first thing that many people don't realize is that messaging and mobile is not just messaging. that means messaging is the back bone for a lot of mobile user activity. think how much we use messaging. these services are critical to companies like alibaba beca

joining me now nbc aviation correspondent, tom costelo. so much speculation. news last night on how the change of direction was made at least 12 minutes before the co-pilot said good night. it tells investigators this was intentional and not an accidental move. why is this so significant to investigators? >> it is potentially significant because it could suggest, as you said, that the pilot had some premeditation there. in other words, if they had pre-programmed in the u turn before the radio call saying good night then it would suggest that somebody had already planned the move. i would caution that our own aviation experts have said some pilots are known to pre-program in kind of the u turn as a safety escape. if something goes wrong they can do a u turn. this information, we are told by our government sources, was transmitted via the system by a data burst of information that came down at 1:07 a.m. and then 12 minutes later we had the last radio call. as for the latest developments today off the coast of australia by about 1,500 miles it's a three-hour flig

about the two men who boarded the malaysian airlines flight using stolen passports and nbc's tom costelo coverses aviation for us. tom, good morning to you. >> good morning. the fourth day for the search for this missing plane is now wrapping up in asia and still nothing. one of the most baffling events in aviation history upon. now malaysian authorities are considering whether there was a mechanical issue or did someone onboard have a psychological problem? >> for the first time this morning we're getting a look at the two iranian men who boarded flight 370 with stolen passports. malaysian authorities released these photos of delavar seyed mohammed reza and pure i nour mohammadi who was trying to get to germany to be with his mother. they were traveling with stolen passports bought at a travel center by an iranian businessman, both booked as one-way to europe. >> we have been checking and we believe that he is not terrorism. >> while u.s. officials see no connection to terrorism, the malaysian officials speculated about possible scenarios. >> one is hijacking, two is sabotage, three, ps