The unresponsive aircraft had set off from Elizabethtown in Tennessee on Sunday, before inexplicably turning around while making its way over New York's Long Island.

It had been heading for the island's MacArthur Airport, but instead found itself over DC - including some of the most heavily restricted airspace in the country - before crashing into mountainous terrain near Montebello, Virginia.

It is not known why the plane, called Cessna Citation, changed course - nor why it failed to answer radio calls.

Federal Aviation Administration officials also do not know how many passengers were on board, though the plane can carry between seven and 12.

There were no survivors found at the wreckage.

Fighter jets were deployed to intercept the plane as it travelled across DC, but were not the cause of the crash.

They were, however, responsible for the loud, house-shaking boom over the US capital after being cleared to travel at supersonic speeds.

A statement from North American Aerospace Defense Command said the F-16s used flares to try to get the wayward plane's attention, but failed to do so.

A source familiar with the matter told Reuters the Cessna was believed to be on autopilot.

Flight tracking websites showed it suffered a spiralling descent at more than 30,000 feet per minute, before crashing down into the St Mary's Wilderness at around 3.30pm local time on Sunday.

The New York Times reports that it was registered to Encore Motors of Melbourne Inc, which is based in Florida.

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In the aftermath of the sonic boom, locals headed to social media to find out what had happened.

Cole Rojewski, a Washington DC lobbyist, tweeted: "Huge boom or explosion in Washington DC a couple of minutes ago. Seems people from Northern Virginia to Maryland heard it. Shook homes here on Capitol Hill. Does anyone know what it was?"

Others suggested that the city might have been struck by an earthquake, while some reportedly called 911.

The Department of Homeland Security tweeted soon after the sound: "We are aware of reports from communities throughout the National Capital Region of a loud 'boom' this afternoon. There is no threat at this time."

Eventually, the Office of Emergency Management of the city of Annapolis, 30 miles to the east of the capital, said the sound was the result of a military exercise.

The White House said President Joe Biden had been briefed on the incident.