Transcript for Investigators unearth remains of Ethiopian Airlines jet

latest on that deadly plane crash in Ethiopia that killed 157 people including eight Americans. Moments ago Austin Singapore joined the growing list grounding that Boeing jet. More than 20 airlines around the world grounding those planes and take a look at the flight radar. Those are the Boeing 737 max 8s in the air right now. It has been involved in two deadly crashes in just the last couple of months and now some leaders here in the U.S. Are also calling for airlines to ground the plane while the investigation is under way. American investigators are on the scene now in Ethiopia. So is our chief national correspondent Matt Gutman. He starts us off. Good morning, Matt. Reporter: Hey,esen authorities are in possession of those flight recorders but you see these hundreds of people behind me, it is their job to pick up the pieces of the fuselage. You can see how small some of them are. Check them out here. All over this field shredded. They're putting them into piles for an investigation that is going to last many weeks here. This morning, crews cutting into the soil with excavators in the grim task of unearthing the remains of that doomed ethiopian airlines jet. First responders delicately picking through what's left of the personal belongings of the 157 people who died on board. American investigators now among those on the ground trying to determine what brought flight 302 down just six minutes after takeoff. Witnesses describe seeing smoke coming from the rear of the plane before it crashed. It hit the Earth with such force most of what's left is in this crater. Investigators hope the black boxes will reveal what happened inside the cockpit both before and after the plane disappeared from radar. That plane never topping 1200 feet off the ground. Absolutely critical that the black boxes that were recovered get read immediately so we can figure out whether this was a problem with the airplane that affects the fleet worldwide. Reporter: This is now the second crash for a Boeing max 8 in less than six months. Last October a lion air jet engaged a nose down dive into the java sea after the pilots failed to disengage the autopilot killing everyone on board. As investigators race to find answers, families around the world are in mourning. The victims from 35 different countries, 22 staffers from the U.N. And there were eight Americans. Among them Antoine Lewis of Madison. His family says he was a proud father and captain in the army. He went doing the things he loved, that he had a passion for and his package was just to make a better world. Reporter: And from Redding, California, Melvin and Bennett Riffel, two brothers on vacation. Melvin leaves behind his pregnant wife, she's due in may. You can see the pieces of the fuselage have been put in this pile right here and a lot of the work in this field is technical but these workers are also dealing with the remains of humans on this flight and that is obviously something that is much more difficult for them to deal with. Guys. Yeah, that is just

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