An American Airlines regional jet went down in the Potomac River near Ronald Reagan Washington National Airport.

National Transportation Safety Board Chairwoman Jennifer Hommendy described the investigation into the crash Wednesday night as an “all-hands-on-deck event” for the agency during a news conference Thursday in which she appeared with members of the board and a senior investigator overseeing the probe.

Ryan O'Hara, 29, was the crew chief of the Black Hawk helicopter that collided with the passenger plane, according to CBS News. He leaves behind a wife and one-year-old son, his local Reserve Officers' Training Corps (ROTC) program said in a social media post confirming his death.