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.

A commercial American Airlines flight crashed into the Potomac River on Wednesday night after a midair collision with a Black Hawk helicopter near D.C. According to The Wall Street Journal, the plane was carrying 64 passengers,

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