The Lockerbie bomber Abdelbaset Ali Mohmed al-Megrahi left Britain aboard a plane for Libya on Thursday following release from prison in Scotland on compassionate grounds.

Scottish Justice Secretary Kenny MacAskill formally announced Megrahi's release in Edinburgh, saying the man, who has terminal prostate cancer, was allowed to return to Libya to die after serving eight years of a 27-year minimum sentence on charges of murdering 270 people in Britain's worst terrorist episode.

MacAskill said he made the decision because medical experts suggested the Libyan had less than three months to live.

MacAskill's announcement came almost 21 years after a bomb smuggled onto Pan Am Flight 103 exploded at 31,000 feet (9,449 meters) over the Scottish town of Lockerbie on Dec. 21, 1988. The bombing killed 259 people on board and 11 on the ground. Of the dead, 189 were Americans.

"I am conscious there are deeply held feelings and that many will disagree whatever my decision. However, a decision has to be made," MacAskill said.

"Scotland will forever remember the crime that has been perpetrated against our people and those from many other lands, the pain and suffering will remain forever," he added.

The justice secretary said it was his decision, and his alone, that Megrahi "be released on compassionate grounds and be allowed to return to Libya to die."

The Libyan was told of the decision at 1 p.m. local time and arrangements were being made for him to travel to Glasgow airport, where a private plane sent by Libyan leader Muammar el-Qaddafi would take him to Libya.

Megrahi, a 57-year-old former Libyan intelligence agent, dropped an appeal of his conviction earlier this week, paving the way for his release.

US Secretary of State Hillary Clinton phoned MacAskill earlier, urging him not to release Megrahi. Seven US senators wrote a letter with a similar message.

It was reported that the White House expressed deep regrets over the decision to release Megrahi.

A special Scottish court that heard the case in the Netherlands in 2001 convicted Megrahi of murder and other offenses related to the bombing but acquitted another Libyan tried with him.

Megrahi has never admitted guilt and this year was appealing his conviction for a second time when he was diagnosed with terminal prostate cancer.

(Xinhua News Agency August 21, 2009)