Aviation experts have warned for years about near collisions at airports around the US, citing air traffic control shortages and airspace congestion.

ARLINGTON, Va. (AP) — All 64 people aboard an American Airlines jet that collided with an Army helicopter were feared dead in what was likely to be the worst U.S. aviation disaster in almost a quarter century, officials said Thursday.

D.C. police confirmed a crash had taken place over the Potomac and that search and rescue operations were taking place in the river. Donald Trump later weighed in.

Several witnesses are speaking out after seeing smoke and sparks in the air as an American Airlines plane collided with a U.S. Army Black Hawk helicopter on its approach to the airport

Political leaders had warned about the dangers of Ronald Reagan Washington National Airport in Washington, D.C. months before an American Airlines flight collided with a U.S. Army Black Hawk helicopter on its approach to the airport.

Without providing any evidence, Trump harshly attacked Democrats for supposedly lowering standards for air traffic controllers, which he suggested could have led to the crash.

"Just the horror that the parents are going through. It just that blows me away. It makes me so sad for the families," said Joanne Kispert, 74, whose father died in the 2001 crash of American Airlines Flight 587 in New York in 2001.

Robert Isom said said airline is focused on passengers, crew members, first responders, families and loved ones.

The Black Hawk is a US Army workhorse helicopter. It has been flying for decades. One tragically collided with a passenger jet this week.

An American Airlines plane and an Army helicopter collided Wednesday night near Ronald Reagan Washington National Airport.

The pilot of the American Airlines plane that crashed into an Army Helicopter on Wednesday was identified as Sam Lilley.