WASHINGTON – F-16 fighters from the D.C. National Guard scrambled Sunday at supersonic speed to intercept a private plane whose pilot was unresponsive, according to North American Aerospace Defense Command.

The fighters intercepted the Cessna 560 Citation V plane at about 3:20 p.m., and it crashed near the George Washington National Forest in Virginia. The pilot never responded to attempts to establish communication, according to Northern Command. 

U.S. Capitol Police officials said they were working with federal partners to monitor the unresponsive pilot as the plane flew near the National Capital Region on Sunday afternoon. According to Capitol Police, the U.S. Capitol Complex was “briefly placed on an elevated alert until the airplane left the area.”

Search efforts by state and local agencies were underway for several hours. By Sunday night, no survivors were found and Virginia State Police suspended search efforts.

The intercept caused sonic booms heard across the Washington region, and the fighters also fired flares to get the pilot’s attention, according to NORAD. Officials in Bowie, Maryland, and the Annapolis Office of Emergency Management in Maryland said the sound was from a sonic boom from an aircraft flight, with the former reporting that the plane was from Joint Base Andrews.

“The loud boom that was heard across the DMV area was caused by an authorized DOD flight. This flight caused a sonic boom,” the Annapolis Office of Emergency Management said on Twitter. “That is all the information available at this time.”

The D.C. Homeland Security and Emergency Management said they were aware of reports from community members throughout the National Capital Region and that there “is no threat at this time.” People flooded social media with posts speculating the source of the ground-shaking sound, with several users reporting the boom shook their homes and rattled their windows.

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FAA, additional agencies investigating crash

The Federal Aviation Administration said in a statement Sunday that a Cessna Citation crashed into mountainous terrain near Montebello in southwest Virginia around 3:30 p.m.

The plane departed from Elizabethton Municipal Airport in Elizabethton, Tennessee, and was bound for Long Island MacArthur Airport in New York, the agency said. But the plane turned around over Long Island and flew a straight path down over D.C.