An American Airlines regional jet went down in the Potomac River near Ronald Reagan Washington National Airport after colliding with a U.S. Army Black Hawk helicopter, Wednesday night, prompting a multi-agency search-and-rescue operation, according to officials.

Hundreds of families are in mourning after an American Airlines regional jet collided with a U.S. Army Black Hawk helicopter on Wednesday night, with both aircraft plunging into the Potomac River near Washington,

Preliminary flight data from the deadly plane crash near Reagan National Airport in Washington, D.C., shows conflicting readings about the altitudes of a passenger jet and Army helicopter that collided,