"Apparently this was a plane that was stolen from SeaTac Airport".
He told authorities on the ground he "would like to apologize" to people who cared about him.
Alaska Airlines CEO Brad Tilden said the man had been "background checked".
The air traffic control staffer assures him they don't have that, and says they just want to find a safe place for him to land.
He told air traffic controllers: "Those guys will rough me up if I try and land there".
Horizon Air COO Constance von Muehlen said she believed the plane had been taken by "a single Horizon Air employee" and that no other passengers or crew were on board.
On Saturday, investigators from the National Transportation Safety Board, FBI, and Alaska Airlines - which operates Horizon Air - travelled to the crash site, which is on a sparsely populated wooded island that is only accessible by ferry.
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Maybe it was the ban on that long putter, or maybe it was some problems with his swing that sent him churning through coaches. Scott was close with fellow Australian Jarrod Lyle, who twice beat cancer while working his way onto the PGA Tour.
"I was naturally surprised that an employee could access an aircraft or an employee that isn't a pilot could do something with the aircraft", said Jeff Price, professor of aviation and author.
The regional airliner was intercepted by a pair of F-15s which the Air Force said were in the air within a few minutes of it taking off. Confirming this, the airport said, "No passengers were onboard during the incident and normal operations have resumed at the airfield". As often happens in situations like these, some information reported early may turn out to be inaccurate.
The pilot, identified by local law enforcement as a 29-year-old ground service agent for Alaska Airlines sister carrier Horizon Air identified only as "Rich", sent several distraught transmissions while piloting the aircraft over open frequencies.
Authorities from the Federal Bureau of Investigation, the Federal Aviation Administration, and the National Transportation Safety Board are now investigating the incident, with the FBI leading the investigation. At one point he said that he had hoped he could have a "moment of serenity" in the air but that everything moved by too fast.
A nearby military base dispatched two F-15 fighter jets, who diverted the aircraft away from residents, before it crashed into a nearby island.
Sheriff's officials say a man who stole an Alaska Airlines plane from an airport in Washington state was "suicidal" and there is no connection to terrorism.
Besides his other duties, he was qualified to tow aircraft, said Gary Beck, Horizon Air's president and chief executive officer.
Experts say the crash exposed alarming gaps in airport security, and is likely to prompt a major review industry security measures.