SAN FRANCISCO, Aug. 10 (Xinhua) -- A passenger plane stolen and driven by an airline employee crashed in Washington state late Friday, according to airport officials.

An airline employee conducted an unauthorized take-off without passenger at Seattle-Tacoma international airport, officials at the airport said in a tweet.

The 76-seat turboprop aircraft belonging to Alaska Airlines crashed in south Puget Sound in Southwest Washington, the officials added. Normal operations at the airport have resumed.

The Pierce County Sheriff's Office said preliminary information suggested that a mechanic had stolen the aircraft and did "stunts in air or lack of flying skills."