LOCKERBIE, UNITED KINGDOM - DECEMBER 17: A member of the public visits the Lockerbie memorial on December 17, 2008 in Lockerbie, southern Scotland. A terrorist bomb caused Pan AM Flight 103 to crash almost 20 years ago on December 21, 1988, with parts of the wing and fuel tanks landing in the town and killing 11 residents. The police investigation that followed into the air disaster, which also killed 259 passengers on the plane, was the biggest in Sottish history and subsequently became a murder inquiry when evidence found it was caused by a bomb.