Washington, Jan 31 (IANS): An internal report by the Federal Aviation Administration suggested that the controller on duty when the deadly aircraft collision happened in Washington, D.C. was doing a job usually handled by two people, US media reported.

Staffing at the air traffic control tower at the Ronald Reagan Washington National Airport was "not normal" during the deadly late-night crash between a passenger jet and an Army helicopter that killed 67 people, The New York Times quoted a preliminary report as saying on Thursday.

The report said the controller who was handling helicopters in the airport's vicinity on Wednesday night was also instructing planes that were landing and departing from its runways -- jobs typically assigned to two different controllers, Xinhua news agency reported.

At a press conference in the White House earlier on Thursday, US President Donald Trump said that there were some warnings prior to the midair collision of a passenger plane and helicopter near the airport Wednesday night, "but the warnings were given very, very late."

Trump said he had heard "very scary tapes".

"When the air traffic controller said, he was talking about, do you see him? But there was very little time left when that was stated," Trump said, adding that there is also "a pilot problem" from the standpoint of the helicopter.

Also at the press conference, Trump confirmed there are no survivors in the collision, and "the work has now shifted to a recovery mission".

John Donnelly, chief of the District of Columbia Fire and Emergency Medical Services Department, told a press conference at the airport on Thursday morning that 28 bodies had been found, including 27 people from the plane and one from the helicopter.

US Transportation Secretary Sean Duffy said on Thursday that the flight paths of the two aircraft were not unusual for the area and that both the helicopter and the airplane had been flying standard flight patterns.

Of the three major airports in the region, Reagan National is closest to the capital. Because of the short length of its runways, more than 90 per cent of flights use its main runway, making it the busiest in the US, with over 800 daily takeoffs and landings.

Duffy said the Federal Aviation Administration would "take appropriate action if necessary to modify flight paths" to ensure adequate separation between civilian airplanes and military helicopters.

US Defence Secretary Pete Hegseth said an investigation had been launched by the Army and Defence Department.