Transcript for Investigators hope mysterious pings will lead to jet's black box

And there are new developments into the new Boeing jet that crashed right into the ocean. Investigators are now hearing pings that could lead them to the black boxes of that lion air jet, and possible clues about why the brand new plane plunged into the sea. ABC's Bob woodruff tonight reporting from Jakarta. Reporter: Tonight, Indonesian investigators hoping pings detected at sea could help lead them to the most crucial element needed for their investigation, the black box. Divers already bringing back shiploads of debris and also body bags. Identifying the first victim, a 24-year-old woman. One of 189 on lion air flight 610. This video given to ABC showing passengers boarding an hour before the tragedy. One man showing us this photo. He is on the left, but took a different flight, those three in the middle, feared lost. The Boeing 737 max 8, which plunged 13 minutes after takeoff, was in service for only two months. Lion air claims a mechanical issue the day before the accident was resolved. Now, authorities appear to be ruling out terrorism, leaning towards technical failure. But with these types of aircrafts in use in the united States, the race is on to find out what brought down that plane after it left this airport. David? Bob woodruff from Jakarta. Bob, thank you.

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