US Probing Stolen Plane Crash In Seattle

The FBI is looking into the man's background. Investigators are trying to find how he got on the plane.

US Federal authorities are continuing to seek what drove an airline worker to steal an empty plane from Seattle's airport in a security scare that caused the scrambling of airforce fighter jets and ended when the plane crashed onto a sparsely populated island.

A Horizon Air ground service agent climbed entered a Bombardier Q400 turboprop aircraft on Friday night in a maintenance area at Seattle-Tacoma International Airport and took off, Horizon sister carrier Alaska Airline said.

He flew for about one hour, often erratically, before crashing on Ketron Island in Puget Sound, about 40 kilometres to the southwest.

The 29-year-old man, who has not been named, appeared to have acted alone, according to the Pierce County Sheriff's Department, which said the employee was believed to have been killed in the crash.

"Doing stunts in air or lack of flying skills caused crash into Island," the Sheriff's Department said on Twitter.

In partial recordings of his conversations with air traffic controllers, the man said he was sorry to disappoint people who cared about him and described himself as a "broken guy".

"Got a few screws loose, I guess," he is heard saying in the recording. "Never really knew it until now."

The Federal Aviation Administration, the Federal Bureau of Investigation and the National Transportation Safety Board were investigating the incident.

"Until the FBI has the opportunity to get better background on the person, find out what motive they had, it's a little too early to make a determination on what the objective was," Debra Eckrote, the NTSB's western Pacific region chief, said.

"He's ground support so they have access to aircrafts," she said of the man.

Two F-15 fighter jets took to the air from a base in Portland, Oregon, and were on the scene within minutes. The jets were armed but did not open fire, North American Aerospace Defence Command, spokesman Cameron Hillier said.

Instead, the F-15 pilots and air traffic controllers tried to guide the plane west, away from populated areas, said Hillier. No one was hurt on the ground, authorities said.

It was unclear how the employee was able to taxi the plane on a runway and take off without authorisation.

Plane Crashes After Being Stolen From Seattle Airport

The sheriff said earlier the employee was an airline mechanic but the airline said he was a ground service agent.

Fire crews were working on putting out the fire from the crash on Ketron Island in Puget Sound. No one was injured on the ground, authorities said.

"We're working to find out everything we possibly can about what happened," Brad Tilden, chief executive of Alaska Air Group, said in a statement.

The FBI is looking into the man's background and try to determine his motive, she said. Investigators are trying to find how he got on the plane.

Investigators expect they will be able to recover both the cockpit voice recorder and the event data recorder from the plane.

White House Press Secretary Sarah Sanders said that President Donald Trump is "monitoring the situation".

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