WASHINGTON: Air traffic controllers lost contact shortly after takeoff with the pilot of a light plane that caused a security scare on Sunday when it flew over heavily restricted airspace near Washington, authorities said on Monday.

Four people including the pilot of the Cessna Citation 560 were killed in the crash, the Federal Aviation Administration (FAA) said. The Department of Defense scrambled F-16 fighter jets, which created a sonic boom over the U.S. capital as they pursued the Cessna.

The National Transportation Safety Board (NTSB) said the Cessna took off from Elizabethton, Tennessee at 1:13 p.m. EDT (1713 GMT) headed to Long Island MacArthur Airport, about 50 miles (80 km) east of Manhattan. Controllers lost communication with the airplane during its ascent.

The last air traffic control communication attempt with the airplane was at around 1:28 p.m., NTSB added.

The FAA said it reported the failure of the pilot to respond to controllers to the domestic events network that includes military, security and law enforcement agencies at around 1:36 p.m.

Officials said the plane appeared to be on autopilot. The NTSB said the airplane was at 31,000 feet and eventually climbed to 34,000 feet, where it remained until 3:23 p.m. when it began to descend. The airplane crashed at approximately 3:32 p.m. in a heavily wooded mountainous section of southwest Virginia.

The NTSB said the Cessna overflew the MacArthur airport at 2:33 p.m. while at 34,000 feet.

The NTSB said investigators do not yet know why the plane was on its specific flight path after overflying the destination airport.

NTSB investigator Adam Gerhardt said the wreckage was highly fragmented and in heavily wooded terrain that made it "a very challenging accident site." The NTSB will remove wreckage and move it to a secure location in Delaware.

The crash is reminiscent of other incidents involving unresponsive pilots. Golfer Payne Stewart died in 1999 along with four others after the aircraft he was in flew thousands of miles with the pilot and passengers unresponsive. The plane eventually crashed in South Dakota with no survivors.

In the case of Stewart's flight, the plane lost cabin pressure, causing the occupants to lose consciousness because of oxygen deprivation.

The Cessna was registered to Encore Motors of Melbourne, Florida, according to FAA flight records.

Encore owner John Rumpel told the Washington Post his daughter, a grandchild and her nanny were on board.

The U.S. military attempted to contact the pilot, who was unresponsive, North American Aerospace Defense Command (NORAD) said in a statement. Military pilots also used flares in an attempt to get the pilot's attention.

The Cessna was not required to have a flight data recorder or cockpit voice recorder, NTSB said.