A passenger plane with 64 people on board has collided with a military helicopter and crashed into a river in Washington.

So far, 18 people have been pulled from the Potomac River, with search and rescue teams working to find the others. It is not yet known if there are any fatalities, REL writes.

Temperatures are reported to be extremely low.

US authorities are investigating the case while Washington's Ronald Reagan National Airport has halted all flights.

What happened?

At around 21:00 p.m. local time on Wednesday, a PSA Airlines plane, operating as American Airlines Flight 5432, collided with a U.S. military helicopter as it approached Ronald Reagan Airport, according to the Federal Aviation Administration.

The passenger plane, a Bombardier CRJ700, departed from Kansas.

There were 60 passengers and four crew members on board, according to American Airlines.

The Pentagon said the helicopter was a Sikorsky H-60, which had taken off from Virginia. Three soldiers were on board, according to the CBS television network.

The Federal Aviation Administration has said it will investigate the incident, along with the National Transportation Safety Board.

Are there victims?

There are no official reports of casualties. Initial reports in US media said the passenger plane split in two in the Potomac River, while the helicopter overturned in the water.

Police and the fire department are searching the river for survivors.

Search and rescue efforts can be seen from Ronald Reagan Airport, which is near the river.

What did the witnesses say?

Ari Schulman told NBC Washington that he saw the plane crash while driving near the airport.

He said the plane's landing seemed normal until he saw a large light in the sky as a result of the collision.

Statements by American officials

US President Donald Trump has said he has been fully briefed on the "terrible accident" and is monitoring the situation closely.

"May God bless their souls," he said in a statement.

Trump thanked the search and rescue teams for their work.

Vice President JD Vance has called for prayers for those involved in the incident.

Defense Secretary Pete Hegseth and Transportation Secretary Sean Duffy, who were newly appointed to their positions, have said they are monitoring the situation.

American Airlines CEO Robert Isom expressed "deep sorrow" over the crash.

The United States has not recorded a passenger plane accident since February 2009, although a series of incidents in recent years have raised safety concerns.