All 64 people aboard an American Airlines jet that collided with an Army helicopter were feared dead in what was likely to be the worst U.S. aviation disaster in almost a quarter century, officials said Thursday.

An American Airlines regional jet went down in the Potomac River near Washington, D.C.'s Ronald Reagan Washington National Airport after colliding with a U.S. Army Black Hawk helicopter on Wednesday night, with no survivors expected.

The midair collision between an American Airlines flight and the military helicopter involved 67 people and is not expected to have any survivors.

A regional jet carrying 64 people collided with an Army Black Hawk helicopter. Reagan National Airport grounded all flights.

Trump appeared to resume the role of blamer-in-chief in the aftermath of Thursday's fatal plane crash, surveying the tragedy as just another American citizen asking questions, rather than as the leader of a nation dealing with its first commercial air disaster in 15 years.

An Army Black Hawk helicopter collided midair with an American Airlines flight from Wichita, Kansas, at Reagan National Airport on Wednesday.

An American Airlines regional jet collided with a military helicopter as it was approaching Reagan National Airport.

An American Airlines plane and a U.S. Army helicopter collided near Reagan National Airport and crashed into the Potomac River, according to officials.

Trump said the Federal Aviation Administration, National Transportation and Safety Board and the U.S. military will carry out a "systematic and comprehensive investigation."

A grainy snippet of video footage taken in the dark of night, seemingly by an airport CCTV camera, appears to show the fatal mid-air collision of an American Airlines passenger plane and a military Black Hawk helicopter.

A midair collision between an Army helicopter and an American Airlines flight killed all 67 people aboard the two aircraft, officials said Thursday, as they scrutinized the actions of the military pilot and reported that control tower staffing was “not normal” at the time of the country's worst aviation disaster in a generation.