Washington DC.Photo:Chen Mengtong/China News Service via Getty

Helicopters fly in front of the Washington Monument

Chen Mengtong/China News Service via Getty

Four people were killed in a small plane crash in Virginia on Sunday, which caused two F-16 fighter jets to hit “supersonic speeds” in an attempt to intercept an unresponsive pilot.

A two-year-old girl, her mother, the girl’s nanny and the plane’s pilot were killed in the crash, according toThe New York Times. The mother was identified as 49-year-old Adina Azarian, a luxury real estate agent in the Hamptons, according toThe Daily Mail.

Once the jets reached the unresponsive Cessna, flares were used “in an attempt to draw attention from the pilot“ and “may have been visible to the public.”

NORAD said the aircraft was “intercepted at approximately 3:20 p.m.” local time and the “pilot was unresponsive.”  After many attempts to “establish contact with the pilot,” the civilian aircraft crashed near the George Washington National Forest in Virginia, the statement said. “NORAD attempted to establish contact with the pilot until the aircraft crashed.”

Adina Azarian and daughter.Adina Azarian/Facebook

Adina Azarian and daughter

Adina Azarian/Facebook

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While he said he didn’t know much about the crash, he speculated that if the plane had lost pressurization, the four individuals on the plane “would have gone to sleep and never woke up.”

Randall K. Wolf via AP

Rumpel’s wife, Barbara Rumpel, shared photos of her daughter and granddaughter onFacebookSunday, writing, “My family is gone, my daughter and granddaughter.”

First responders who attended to the crash site said the plane left a “crater” and it appeared that the plane hit the ground “at a very steep angle,“CNN reported.

The cause of the crash currently remains unknown, but theNTSBis investigating.

DC Homeland Security & Emergency Managementacknowledged the boom soon after it happened.  “We are aware of reports from communities throughout the National Capital Region of a loud “boom” this afternoon,” the agency tweeted. “There is no threat at this time.”

Karen Hatchl, a teacher in Arlington, was playing frisbee with her kids when they heard a loud noise that “sounded like thunder” even though there “wasn’t a cloud in the sky.” She tells PEOPLE that they “wondered if something had blown up.”

“It was jarring,” she says. “Enough so that I looked for an emergency announcement and radar to see what it could be.”

source: people.com