An American airline carrying 60 passengers and four crew members collided on Wednesday with an Army helicopter while landing at Ronald Reagan National Airport near Washington.
Witness reports confirmed multiple fatalities, but the precise number of victims was unclear as rescue crews search for survivors.
An Army official said three soldiers were onboard the helicopter.
There was no immediate comment on the cause of the collision. However, all operations at the airport were halted as dive teams scoured the site and helicopters while law enforcement agencies across the region flew over the scene in search for bodies.
“We are going to recover our fellow citizens,” District of Columbia Mayor Muriel Bowser said at a sombre news conference at the airport on Thursday morning where she declined to say how many bodies had been recovered.
Senator Roger Marshall of Kansas said, “When one person dies, it’s a tragedy, but when many, many, many people die it’s an unbearable sorrow.”
President Donald Trump said he had been “fully briefed on this terrible accident” and, referring to the passengers, added, “May God Bless their souls.”
The Federal Aviation Administration said the midair crash occurred before 9 p.m. EST when a regional jet that had departed from Wichita, Kansas, collided with a military helicopter on a training flight while approaching an airport runway.
The crash occurred in some of the most tightly controlled and monitored airspace in the world, just over three miles south of the White House and the Capitol.
Investigators will try to piece together the aircraft’s final moments before their collision, including contact with air traffic controllers as well as loss of altitude by the passenger jet.
American Airlines Flight 5342 was inbound to Reagan National at an altitude of about 400 feet and a speed of about 140 miles per hour when it suffered a rapid loss of altitude over the Potomac River, according to data from its radio transponder.
The Canadian-made Bombardier CRJ-701 twin-engine jet, manufactured in 2004 can be configured to carry up to 70 passengers.
A few minutes before landing, air traffic controllers asked the arriving commercial jet if it could land on the shorter Runway 33 at Reagan National which was confirmed by pilots.
Controllers then cleared the plane to land on Runway 33. Flight tracking sites showed the plane adjust its approach to the new runway.
Less than 30 seconds before the crash, an air traffic controller asked the helicopter if it had the arriving plane in sight.
The controller made another radio call to the helicopter moments later: “PAT 25 pass behind the CRJ.” Seconds after that, the two aircraft collided.
The plane’s radio transponder stopped transmitting about 2,400 feet short of the runway, roughly over the middle of the river.
Video from an observation camera at the nearby Kennedy Centre showed two sets of lights consistent with aircraft appearing to join in a fireball.
“I know that flight. I’ve flown it several times myself,” said Sen. Jerry Moran of Kansas.
He said that he expected that many people in Wichita would know people who were on the flight.
“This is a very personal circumstance,” he said.
American Airlines CEO Robert Isom expressed “deep sorrow” over the crash, saying the company was focused on the needs of passengers, crew, first responders and families and loved ones of those involved.
“It’s a highly complex operation,” said D.C. fire chief John Donnelly. “The conditions out there are extremely rough for the responders.”
The U.S. Army described the helicopter as a UH-60 Blackhawk based at Fort Belvoir in Virginia.
The helicopter was on a training flight. Military aircraft frequently conduct training flights in and around the congested and heavily restricted airspace around the nation’s capital for familiarisation and continuity of government planning.
