(NewsNation) — An unresponsive pilot whose plane violated restricted airspace above the Washington, D.C. area caused the U.S. to scramble fighter jets in pursuit of the small aircraft Sunday, officials said. The pursuit caused a sonic boom heard over the capital.

The civilian aircraft later crashed into mountainous terrain in southwest Virginia, officials said. Police confirmed later Sunday night there were no survivors, but did not know how many people were on board.

“Our officials were working closely with our federal partners to monitor an unresponsive pilot who was flying an airplane near the National Capital Region. The U.S. Capitol Complex was briefly placed on an elevated alert until the airplane left the area,” the U.S. Capitol Police tweeted.

The fighter jets caused a sonic boom over the U.S. capital as they raced to catch up with the Cessna Citation, which can carry seven to 12 passengers, per Reuters.

The Federal Aviation Administration believes the aircraft took off from Elizabethtown, Tennessee, on Sunday and was headed for Long Island’s MacArthur Airport. Inexplicably, the plane turned around over New York’s Long Island and flew a straight path down over D.C. before it crashed over mountainous terrain near Montebello, Virginia, around 3:30 p.m.

The fighter jets pursuing the aircraft were authorized to travel at supersonic speeds, according to a statement by the North American Aerospace Defense Command.

“During this event, the NORAD aircraft also used flares – which may have been visible to the public – in an attempt to draw attention from the pilot,” the NORAD statement said. “Flares are employed with highest regard for safety of the intercepted aircraft and people on the ground. Flares burn out quickly and completely and there is no danger to the people on the ground when dispensed.”

NORAD reports they attempted to establish contact with the pilot until the crash.

“A Cessna Citation crashed into mountainous terrain near Montebello, Va., around 3:30 p.m. local time on June 4. The aircraft took off from Elizabethton Municipal Airport in Elizabethton, Tenn., and was bound for Long Island MacArthur Airport in New York,” the FAA said in a statement.

A U.S. official said the jet fighters did not cause the Cessna Citation to crash, Reuters reported.

Washington D.C. residents said on Twitter that they heard a large boom, with some saying it shook the ground and walls. Residents as far away as northern Virginia and Maryland reported hearing the noise.

“There is no threat at this time,” the D.C. Homeland Security and Emergency Management said following the incident.

The National Transportation Safety Board and FAA are investigating the incident.

The Associated Press and Reuters contributed to this story.