A US passenger plane carrying 64 people crashed into Washington's chilly Potomac River on Wednesday after colliding mid-air with a military helicopter near Reagan National Airport, prompting a major emergency response and the grounding of all flights. The plane had been about to land after flying from Kansas. American Airlines, whose subsidiary operated the flight, said "there were 60 passengers and four crew members on board the aircraft." A US Army official said the helicopter was a Black Hawk model carrying three soldiers - their status currently unknown. Via AFP.