10:15 PM: 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.
Ed Troyer, a spokesman for the Pierce County Sheriff's Department, says on Twitter Friday night that a 29-year-old airline mechanic stole the Horizon Air Q400 from Sea-Tac International Airport.
Witnesses reported seeing the plane being chased by military aircraft before it crashed near Ketron Island. There were no passengers aboard.
The sheriff's department said they were working to conduct a background investigation on the man, whose name was not immediately released.
The man could be heard on audio recordings telling air traffic controllers that he's "got a lot of people that care about me" and that he is "just a broken guy."
9:50 PM: Officials at Sea-Tac International Airport say an Alaska Airlines plane that was stolen by an airline employee and has crashed in Washington state.
Airport officials say in a tweet Friday night that an airline employee "conducted an unauthorized takeoff without passengers."
Witnesses reported seeing the plane being chased by military aircraft near the airport.
The Pierce County Sheriff's Office said on Twitter that preliminary information suggested that a mechanic had stolen the aircraft. The tweet said the crash may have been caused by the mechanic "doing stunts in air or lack of flying skills."
A Coast Guard spokeswoman said the agency was responding to a report of a smoke plume and possible plane crash. Petty Officer Ali Flockerzi said a 45-foot vessel was headed to the scene.
9:37 PM: Alaska Airlines says there was an "unauthorized take-off" of an airplane and witnesses reported a jet being chased by military planes near Sea-Tac International Airport in Washington state.
The airline tells The Associated Press that the plane was a Horizon Air Q400 and it believed no passengers were on board.
No other information was immediately available.
Horizon Air is part of Alaska Air Group and flies shorter routes throughout the U.S. West.
The Q400 ix a turboprop aircraft with 76 seats.