A "suicidal" airline mechanic stole an empty Alaska Airlines plane and took off from Sea-Tac International Airport in Washington state before crashing near a small island, officials said.
Preliminary information suggests that the 29-year-old mechanic stole the Horizon Air Q400 and the crash occurred because the person was "doing stunts in air or lack of flying skills," the Pierce County Sheriff's Department said.
Witnesses reported seeing the plane being chased by military aircraft before it crashed near Ketron Island, southwest of Tacoma, Washington.
There were no passengers aboard.
Ed Troyer, a spokesman for the Pierce County Sheriff's Department, said on Twitter that the man was suicidal and there was no connection to terrorism.
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 is "just a broken guy."