The U.S. Army helicopter that collided with a passenger jet in Washington was being operated on a training flight by a "fairly experienced crew" with night-vision goggles, Defense Secretary Pete Hegseth said on Thursday,

Defense Secretary Pete Hegseth announced the Pentagon has begun a probe into the cause of a deadly midair collision between a passenger jet and a military helicopter, looking to understand who was to blame and how the tragedy occurred.

Pete Hegseth, chief of the Defense Department, announced Thursday that the Pentagon and Army are investigating the collision over Ronald Reagan Washington National Airport in an unexpected first test for the newly minted secretary.