Hundreds on Sunday commemorated the 20th anniversary of the Lockerbie bombing in which terrorists blew up a US airliner over Scotland, killing 270 people, dpa reported.
Pan Am Flight 103 from London to New York exploded in the skies above the Scottish town of Lockerbie on December 21, 1988. All occupants, as well as 11 people from the town, were killed.
Memorial services were held on Sunday in Lockerbie, Heathrow - from where the aircraft took off - and the United States.
Relatives of the victims and government officials were among those marking the event. Scottish First Minister Alex Salmond and Britain's Scottish Secretary Jim Murphy addressed the gathering.
"This was the worst terrorist attack on the United Kingdom," Murphy said. His thoughts were with the families who had lost loved ones in the attack, he added.
Religious services were set for 7 pm (1800 GMT), the time the bomb tore through the Boeing 747 at an altitude of 10,000 metres.
In 2001, former Libyan intelligence agent Abdel al-Megrahi was convicted of mass murder in a special Scottish court in the Netherlands.
The 56-year-old, who denies having smuggled the bomb onboard the aircraft, is due to serve another 20 years in prison before being eligible for parole.
His is suffering from advance stage prostate cancer and has been trying to secure early release.
In 2002, al-Megrahi failed in his attempt to appeal against his conviction, but the case was referred for review and negotiations could start in the coming year.
