Transcript for Video shows US soldiers weeks before deadly Niger attack

And we have new reporting tonight, new images here in the investigation into a deadly ambush in Niger, and the death of four American soldiers. National geographic tonight with never before seen images prior to that fatal mission. Here's ABC's chief global affairs correspondent Martha Raddatz tonight. Reporter: This is 25-year-old ladavid Johnson, just weeks before he and three other Americans would be ambushed and killed. The tattoo across his chest, myeshia, his wife. And here he is with nigerien soldiers his unit was tasked to train. Johnson was the mechanic, and the self-appointed unit barber. Is there something you haven't been able to fix or do that you've been asked to do on this trip? Negative, sir. Not yet. Not yet? Okay, well, if you figure out what that is, let us know and we'll make sure you get trained on it. Or you can just watch YouTube like you did with haircutting. Yes, sir. Reporter: And this is staff sergeant Dustin Wright, an explosives expert practicing his craft. Anybody can shoot a gun, demo is something else. It's a lot more fun. Reporter: The special forces United States had never come under fire, but it is gear from this nat geo video, this was hostile territory. In this area is ISIS, and then in this area, we have boko Haram. Reporter: On October 3rd. Wright, Johnson and nine other others headed out meet local leaders, but on their way back, without air cover, heavy weapons, or heavy armor were sent to a far more dangerous mission.to try to dangerous mission. To try to capture or kill a local terrorist. 24 hours later, they were ambushed. There's never a doubt in my mind how he fought, and what he would do for any member of that team. And I am proud. Those soldiers just days before that mission. Martha Raddatz with us tonight. And Martha, we do know that the Pentagon is expected to release its findings in the coming days? Reporter: That's exactly right, David. It's been an exhaustive investigation as to why that mission dramatically changed. But the families of the fallen will be briefed before it's made public. David? Martha Raddatz, who has been following this from the start, thank you. And the series is on nat geo

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