Thai Airways International Flight 114, a Thai Airways International Boeing 737-400 bound for Chiang Mai from Don Mueang Airport in Bangkok, was destroyed by an explosion of the center wing tank resulting from ignition of the flammable fuel/air mixture in the tank while the aircraft was parked prior to boarding on the ground on 3 March 2001. Officially, the source of the ignition energy for the explosion could not be determined with certainty, but the most likely source was an explosion originating at the center wing tank pump as a result of running the pump in the presence of metal shavings and a fuel/air mixture. One flight attendant died.