The airspace around Washington, D.C., is congested and complex — a combination aviation experts have long worried could lead to catastrophe.

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.

On Tuesday, a day before Wednesday’s fatal collision, a Republic Airways jet from Windsor Locks, Conn., was minutes away from landing at Ronald Reagan Washington National Airport before it aborted its landing to avoid a helicopter in its way.

An American Airlines jet with 60 passengers and four crew members aboard collided Wednesday with an Army helicopter while landing at Ronald Reagan National Airport near Washington, prompting a large search-and-rescue operation in the nearby Potomac River.

A jet with 60 passengers and four crew members collided with an Army helicopter while preparing to land at Ronald Reagan National Airport near Washington, D.C., sending the aircraft plummeting into the Potomac River and killing everyone on board.

At about 9pm local time (02:00 GMT) on Wednesday, an inbound American Airlines aircraft (flight 5342), manufactured by the Canadian firm Bombardier, collided with a Sikorsky Black Hawk army helicopter as it approached the Ronald Reagan airport, located along the Potomac River southwest of Washington, DC.

There were no survivors after a collision between an American Airlines passenger jet and an Army helicopter at Ronald Reagan Washington National Airport near Washington, D

Sixty-seven passengers and crew died in Wednesday night's crash between a regional American Airlines jet and a Blackhawk helicopter from Fort Belvoir near Reagan National Airport.

It collided with a military helicopter on a training flight while landing at Ronald Reagan National Airport, near Washington DC. The airport's runways have since been closed while a search for survivors takes place.

As the American Eagle Flight 5342, a CRJ jet, approached the helicopter, the tower controller asked the helicopter pilot if he had the CRJ in sight. The helicopter pilot cannot be heard responding to the question before the two aircraft collided.

Washington DC's Ronald Reagan Airport has suspended all aircraft take-offs and landings in response to the incident at the airfield