An airline employee stole a passenger plane Friday from the Seattle-Tacoma International Airport and flew it for an hour with military jets chasing him, pulling off aerobatic stunts before crashing in a wooded island 25 miles away, authorities said.
The 29-year-old Horizon Air ground service agent -- the only person aboard -- died, the Pierce County Sheriff's Department said, without further identifying him.
The incident, which the FBI's Seattle office did not consider terrorism, raises questions about airport security. Investigators headed Saturday to the crash site to recover the plane's data recorders and the man's remains as part of a criminal probe, authorities said.
The 76-seat Horizon Air turboprop plane took off without authorization around 8 p.m. local time, witha Horizon Air employee who was not a pilot at the controls, airport officials tweeted.
After "doing stunts in (the) air" -- or being flown without proper skills -- for about an hour, the plane crashed at Ketron Island, the sheriff's department said. The man was a ground service agent, a job that includes directing aircraft for takeoff and gate approach, handling baggage and de-icing planes, authorities said.
Video from a witness on the ground shows the plane at one point doing a loop, putting the aircraft upside-down, then pulling up just feet above a body of water.
In light of the incident, airports nationwide will look at whether their security procedures need to change, CNN safety analyst David Soucie said. For one, the man shouldn't have been able to board the plane alone, he said.
"There is a protocol to not allow anyone singularly to get onboard an aircraft," Soucie said. "If you're going to access the aircraft ... you make sure that you check with someone else, and that someone else (will confirm) that ... you have the right authority to get onto that aircraft."
This will be a major learning event for the aviation industry, CNN aviation analyst Justin Green said.
'I would like to apologize ... got a few screws loose'
In audio recordings of the incident posted on Broadcastify, the man can be heard talking to air traffic controllers as they try to guide him to land the plane.
At one point, he apologizes and says he is a "broken guy" with "a few screws loose."
"I've got a lot of people that care about me, and it's going to disappoint them to hear that I did this," the man says. "I would like to apologize to each and every one of them. Just a broken guy, got a few screws loose, I guess. Never really knew it until now."
The sheriff's department described the man as suicidal. It did not elaborate.
Earlier in the flight, the man says: "This is probably, like, jail time for life, huh? I mean, I would hope it is, for a guy like me."
"Well," a controller responds, "we're not going to worry or think about that. But could you start a left-hand turn, please?"
Later, a controller discusses getting a pilot on the radio to help the man control the aircraft.
"Nah, I mean, I don't need that much help. I've played some video games before," the man responds.
Also, there was this exchange:
"Congratulations," an air traffic controller says, "you did that, now let's try to land that airplane safely and not hurt anybody on the ground."
The man responds: "Awwww-right ... dammit.. I don't know man! I don't know! I don't want to. I was kinda hoping that was gonna be it. Ya know?"
The plane eventually crashed on sparsely populated Ketron Island, starting a fire in the woods but injuring no one outside the plane. The fuselage was fragmented and appeared to be upside down,said Debra Eckrote, regional chief for the National Transportation Safety Board.
F-15 jets chased the plane
The plane was a Q400, a Bombardier turboprop plane, one of about 40 the airline has in its fleet.
Within minutes of the plane's takeoff, the military scrambled two armed F-15 jets from Oregon to follow it, according to local and airline authorities and two sources with knowledge of the situation. They pursued the aircraft before it went down on Ketron Island, between Tacoma and Olympia.
"NORAD fighters did not fire upon the aircraft," North American Aerospace Defense Command said Saturday morning in a news release. The jets' capability was appropriate to the potential task, one of the sources said, without offering details.
F-15 "pilots kept plane out of harms way and people on ground safe," the sheriff's office tweeted. The jets were not involved in the crash, it said.
The cause of the crash wasn't immediately known, but the F-15s did not bring the plane down, Eckrote said.
Witness thought it was an air show
Witnesses described the surreal scene after the plane left the airport. John Waldron was walking along a trail near the bay when he noticed the two military jets following a plane doing aerobatics.
"I thought they were practicing for an air show," he said.
After the plane approached Ketron Island, Waldron saw a thick column of smoke followed by a loud explosion, he said.
"Everyone was literally frozen in place, muttering about what possibly happened," he said.
Kethleen Reichel said she watched the planes pass by for about two minutes.
"My husband and I are recently former Boeing employees, and we were wondering why a jet was near the passenger airplane," she said. "We heard the jet because our windows were down while we were waiting in the ferry line to go to Anderson Island, which is adjacent to Ketron Island."
He had some flight skills, expert says
It wasn't immediately clear what training, if any, the man had in flying planes.
A ground service agent's tasks don't involve touching planes' controls, CNN aviation analyst Mary Schiavo said.
But the plane made turns and aerobatic maneuvers that suggest some skill, she said.
"In this plane, he certainly knew how to retract the landing gear, he coordinated both engines, powered them up to get a coordinated takeoff," she said. "A couple of the turns, it looked like what we call in basic flight training a 'coordinated turn,' meaning that he not only used the yoke ... but you also coordinate with the rudders and you do the turns.
"Yeah, he knew how to fly," she continued. "But ... the air traffic controller had to tell him how to set what they call the 'bugs' -- they're just little, sort of, little levers, or little notches on your indicator for your heading, ... which is kind of basic.
"So, (he) had some knowledge but clearly wasn't a commercial pilot."
Federal agencies are investigating
The plane was taken from a maintenance position and was not scheduled for a passenger flight, said Gary Beck, Horizon Air's president and chief executive officer.
"Our hearts are with the families of the individual aboard as well as all of our Alaska Air and Horizon Air employees," said Constance von Muehlen, the airline's chief operating officer.
The regional airline, based at the Seattle-Tacoma airport, is owned by the Alaska Air Group.
The FBI will lead the investigation, said Eckrote, the NTSB regional chief.
Investigators on Saturday will try to retrieve the plane's flight data recorder and its cockpit voice recorder.
"He might have been talking to himself in the cockpit," so the voice recorder may provide additional information that wasn't recorded in radio traffic, she said.
President Donald Trump was briefed on the incident and is monitoring the situation, White House Press Secretary Sarah Sanders said Saturday morning.