SEATTLE, Wash. -- A Horizon Air plane was reportedly hijacked from a Sea-Tac Airport runway Friday night and was flown around until it eventually crashed in Ketron Island outside of Seattle, according to Federal Aviation Association sources.

Sea-Tac Airport confirmed via Twitter that an airline employee conducted an unauthorized takeoff of a Horizon Air Turbo Prop without passengers on board. Sea-Tac Airport reported that the plane crashed in south Puget Sound.

Alaska Airlines confirmed that a Horizon Air Q400 was involved in an “unauthorized take-off” in a tweet.

“We believe there are no passengers on board,” the tweet said.

The plane crashed into Ketron Island, according to the Pierce County Sheriff's office.

PCSO confirmed in a tweet that the person is a "suicidal male" and is a 19-year-old Pierce County resident. PCSO tweeted that he "was doing stunts in air or lack of flying skills caused crash into Island."

PCSO also said in a tweet that AIr Force F-15s responded to the scene and tried to keep the plane from crashing into an area that would hurt citizens.

Around 8: 15 p.m., multiple viewers of our sister station in Seattle, KING 5, called to report a hijacked airplane, saying an apparent pilot or airport worker took off with an aircraft.

A number of viewers called KING 5 after witnessing the plane crash on Ketron Island. A large plume of smoke is visible to residents surrounding Steilacoom, Washington.

At 9:45 p.m. on Friday,

Flight were delayed but normal operations have since resumed at Sea-Tac Airport.

Two flights were delayed at Spokane International Airport because of the Sea-Tac delay.