CBS News reported that at least 18 bodies had been recovered so far, citing a police official. Two sources told Reuters multiple bodies had been pulled from the water.
American Airlines confirmed that 64 people were aboard the jet - including 60 passengers and four crew members. Three soldiers were aboard the helicopter, a U.S. official said.
Police said multiple agencies were involved in a search and rescue operation in the Potomac River, which borders the airport.
Dozens of police, ambulance and rescue units, some ferrying boats, staged along the river and raced to positions along the tarmac of Reagan airport. Live TV images showed several boats in the water, flashing blue and red lights.
The airport said late on Wednesday that all takeoffs and landings had been halted as emergency personnel responded to an aircraft incident.
U.S. President Donald Trump said in a statement that he had been "fully briefed on the terrible accident which just took place at Reagan National Airport."
"May God bless their souls," he added. "Thank you for the incredible work being done by our first responders. I am monitoring the situation and will provide more details as they arise." Reuters
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