U.S. authorities said on Thursday it was not yet clear why a regional jet crashed into a U.S. Army helicopter at a Washington airport, killing 67 people in the deadliest U.S. air disaster in more than 20 years.

More than 60 people were killed when an American Airlines regional passenger jet collided with a U.S. Army Black Hawk helicopter on Wednesday and crashed into the frigid Potomac River near Ronald Reagan Washington National Airport.

An Army Black Hawk helicopter collided with a regional American Airlines flight that was on approach to Ronald Reagan Washington National Airport near Washington, D.C. on Wednesday night.

“It is the American airport,” said Rep. Norma Torres (D-Calif.), who said Reagan National isn’t just the most convenient airport for lawmakers. “It’s the place where citizens all over the country come to lobby their members of Congress, their US senators on issues of extreme importance to them.”

Multiple fatalities have been reported after a horrific incident involving American Airlines flight 5342 and a U.S. Army UH-60 Black Hawk helicopter over

Figure skaters and coaches returning from the national championships were aboard the American Airlines flight that collided with a Black Hawk helicopter near Reagan National Airport on Wednesday, the U.

A jet carrying 60 passengers and four crew members collided Wednesday with an Army helicopter while landing at Ronald Reagan National Airport in Arlington County, prompting a large search-and-rescue o

An Army Black Hawk helicopter collided midair with an American Airlines flight from Wichita, Kansas, at Reagan National Airport on Wednesday.

Deadly mid-air collision over Washington, D.C., reignites concerns over air traffic congestion and safety risks at Ronald Reagan Washington National Airport

Investigators analyze flight data to understand the crash between an American Airlines jet and a military helicopter and exactly what was going on before disaster struck.

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.