Fighter jets were scrambled to intercept a private aircraft flying over Virginia, close to Washington DC, on Sunday afternoon.
A supersonic boom was heard in Washington and northern Virginia as the jets chased the private plane, whose pilot was “unresponsive”, military authorities said.
The fighter jets also deployed flares in an attempt to attract the attention of the pilot of the private aircraft, a Cessna 500 Citation.
Military authorities said the civilian aircraft was intercepted at about 3.20pm local time (8.20pm Irish time).
They said the pilot of the private aircraft was unresponsive to attempts to contact it.
The civilian plane crashed in Virginia on Sunday afternoon. No survivors were found when rescuers got to the wreckage, the Associated Press reported.
The aircraft is understood to have flown from an airport in Tennessee to Long Island in New York.
US media reported that the civilian aircraft reached Long Island before turning around while airborne.
It then flew over Washington DC, where the airspace is closely monitored and controlled.
When pilot of the Cessna Citation did not respond, military authorities scrambled F-16 jets to intercept.
US media reported that the military jets did not shoot down the civilian aircraft or cause it to crash.
The National Transportation Safety Board said it would investigate the crash.
The Anne Arundel County Office of Emergency Management in Maryland confirmed that the loud boom heard by people in the area was the result of a sonic boom, and said there is no threat associated with the incident. – additional reporting agencies