A "suicidal" mechanic stole an empty passenger plane from the Seattle-Tacoma airport, took it for a brief flight that included an aerial loop, then crashed it and died in an incident officials said was unrelated to terrorism.

Two military F-15s were scrambled to chase the stolen plane, but "were not involved in the crash," local officials said. Video taken by a bystander yesterday showed the passenger airplane making an unlikely upside-down loop, then flying low over Puget Sound before crashing into the sparsely populated Ketron Island in the northwestern US state of Washington.