WASHINGTON (dpa-AFX) - A man who stole an empty passenger plane from Seattle airport and then crashed it was an airline worker with full credentials, authorities said.
The 29-year-old had worked for Horizon Air for more than three years, towing and tidying aircraft and loading bags.
The man, named by US media as Richard Russell, took off late on Friday, forcing the airport to close while two fighter jets gave chase.
After making 'incredible manoeuvres', he crashed the plane and was killed.
The flight lasted 90 minutes and the crash site is on Ketron Island, a sparsely populated area in Puget Sound.
'At this time, we believe he was the only one in the aircraft but of course, we haven't confirmed that at the crash site,' said Jay Tabb, chief of the FBI's Seattle division.
Mike Ehl, director of aviation operations at the airport, said the man 'had access legitimately' to the plane and that 'no security violations were committed'.
Alaska Airlines CEO Brad Tilden said he had been 'background checked'.
'He worked his shift yesterday and we believe he was in uniform,' he added.
Mr Tilden said planes do not have door or ignition keys, and that other airport security measures keep them safe.
Gary Beck, CEO of Horizon Air, said that 'to our knowledge, he didn't have a pilot's licence' and that he had no idea how the man had gained the skills to fly such a 'complex machine'.
Copyright RTT News/dpa-AFX