Ronald Reagan Washington National Airport will be closed until at least 11 a.m. ET Thursday after a passenger jet and a military helicopter crashed

An American Airlines flight crashed into a U.S. Army Black Hawk Helicopter over the Potomac River as it approached Ronald Reagan Washington National Airport.

The crew of the Army Black Hawk helicopter involved in the deadly collision with a jetliner had thousands of hours of flight experience.

An airspace cluttered with passenger planes and military aircraft. A history of near-crashes. And a growing shortage of air traffic controllers available to manage it all. Some experts, politicians and airport managers have been warning for years of the risks posed by the crowded airspace and volume of flights at Ronald Reagan Washington National Airport (DCA).

An American Airlines plane carrying 60 passengers and four crew members collided with an Army Black Hawk helicopter outside Reagan National Airport near Washington, D.C. Wednesday evening. Three soldiers were onboard the helicopter and a massive search and rescue operation is now unfolding in the Potomac River.

Defense Secretary Pete Hegseth said that the military has identified the three soldiers killed in the Black Hawk collision over the Potomac River.

Dozens of people are feared dead after a military helicopter collided with a civilian airliner midair around Washington, D.C.

The airspace around Ronald Reagan Washington National Airport has long been problematic due to heavy military and commercial flight activity in the nation’s capital, according to industry insiders.

American Airlines said the jet had 60 passengers and four crew members, while the Pentagon confirmed that three soldiers were aboard the helicopter. There was no immediate word on fatalities.

The airspace where a deadly mid-air crash between a passenger plane and a U.S. Army Black Hawk occurred late Wednesday night is one of the most complex and congested in the country.

An Army Black Hawk helicopter collided with a regional jet near Ronald Reagan Washington National Airport on Wednesday evening, U.S. officials confirmed to ABC News.