20 years ago today, on 21 December 1988, the Lockerbie air disaster took place.

Pan-Am Flight 103 from Frankfurt to New York via London exploded in the air above the southern Scottish town of Lockerbie. All 259 on board plus 11 on the ground were killed. The cause was a bomb placed in the hold by Libyan terrorists, one of whom is currently serving life imprisonment in a Scottish prison. It was the worst terrorist attack on British soil.