A U.S. airline worker stole an empty passenger plane from the Seattle-Tacoma airport late Friday, took it for a brief flight then crashed it.

Two military F-15s were scrambled to chase the stolen plane, but officials said the jets “were not involved in the crash.”

Video taken by a bystander showed the passenger aeroplane making an unlikely upside-down aerial loop, then flying low over Puget Sound before crashing into the sparsely populated Ketron Island in the northwestern U.S. state of Washington.

The crash sparked a fire in the dense forest. Flames lit up the night as they spread from the burning wreckage to nearby trees. Officials said there were no victims on the ground. The cause of the crash wasn’t immediately known, but the F-15s did not bring the plane down, officials said.

The pilot was identified as Richard Russell, 29, a Horizon Air ground service agent for three and a half years. He was killed in the crash, the Pierce County Sheriff’s Department said. Russell was the only person aboard the plane, the department said.

The stolen plane was a twin-engine turboprop Q400 airplane belonging to its sister carrier Horizon Air, Alaska Airlines said on Twitter. It normally carries 76 passengers.

“This is not a terrorist incident,” Ed Troyer with the Pierce County Sheriff’s office wrote on Twitter.

John Waldron, who took dramatic video of the stolen plane flying in a loop, told CNN that he was out for an evening stroll when he saw the two jet fighters following the turboprop airplane.

His first thought was that they were practising for an air show.

“So, I started to capture video, just because I thought it was, kind of bizarre,” he said. “I thought this is really odd. Kept the video rolling.”

Then the passenger plane pilot “did a complete loop … I couldn’t believe he recovered.”

He estimated that the plane at its lowest point was no more “than 100 feet (30.5 meters) above the water.”

Then the pilot “pulled – pretty much straight up and kind of at an angle and almost stalled the aircraft. Somehow he got it leveled back off and then made his way down toward the island.”

Waldron said he was prepared to “run and take cover.” He briefly turned away, then turned back and saw the explosion as the plane crashed.

“Saw a bright, pinpoint area of flame and the smoke. I thought, oh, my god. I think he just crashed.”

Russell comes across as excitable, confused, and even apologetic in a conversation with the control tower.

“Congratulations, you did it,” the control tower tells Russell, according to audio that aired on CNN. “Let’s turn around the air and land it and not hurt anybody on the ground.”

“I don’t know, man,” Russell answers. “I don’t want to. I was kind of hoping that was going to be it, you know.”

Russell explains that he had put some fuel in the plane “to go check out the Olympics,” but then worried that he was running low.

“I’m down to 2,100 [pounds] (952 kg),” he says, “I don’t know what the burnage is like on take-off, but it burned quite a bit faster than I expected.”

The control tower gently urges him to land at a nearby military base. “I wouldn’t want to do that. They probably have anti-aircraft [guns],” he responds.

“This is probably jail time for life, huh?” he later asks, according to a recording provided by The Seattle Times.

Russell said: “I’ve got a lot of people that care about me. It’s going to disappoint them to hear that I did this. 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.”

Pierce County Sheriff Paul Pastor described the incident at a press conference as a “joyride gone terribly wrong.”

The job of a ground service agent includes directing aircraft for takeoff and gate approach, handling baggage and tidying and de-icing planes, authorities said.

It wasn’t immediately clear what training, if any, Russell 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.

(SD-Agencies)