THE death of Abdelbaset Ali Mohmed al Megrahi, almost three years after his release from a Scottish jail, should not stop the search for the truth about the Lockerbie bombing, victims' families and politicians insisted last night.

The Libyan's son, Khaled, announced the 60-year-old's death at his home in Tripoli yesterday, several days after he is understood to have slipped into a coma.

David Cameron and Alex Salmond both stressed that people's first thoughts should be with the 270 victims of the 1988 atrocity and their loved ones.

The Prime Minister said he had "always been clear" the man convicted of the Lockerbie bombing should never have been released from prison, but noted: "Today is a day to remember the 270 people who lost their lives in what was an appalling terrorist act.

"Our thoughts should be with them and their families for the suffering they have had."

Mr Cameron dismissed fresh calls for an inquiry into Megrahi's conviction, saying: "This has been thoroughly gone through. There was a proper process, a proper court proceeding and all the rest of it. We have to give people the chance to mourn those that were lost.

"I'm very clear that the court case was properly done and properly dealt with."

The decision in August 2009 by Kenny MacAskill, the Scottish Justice Secretary, to release Megrahi on compassionate grounds because medical evidence suggested he had just three months to live has been the SNP Government's most controversial decision to date and sparked fierce criticism at home and abroad.

Mr MacAskill said last night his decision had been based on expert advice and was made "in good faith and following the due process of Scots law".

He added: "This news was not unexpected – Mr Megrahi was diagnosed with terminal prostate cancer, which was the basis on which I released him on compassionate grounds and it confirms what we have always said about his medical condition."

Mr MacAskill added: "It is open for relatives of Mr Megrahi to apply to the Scottish Criminal Cases Review Commission to seek a further appeal [against his conviction]. And the best, indeed the only, place for guilt or innocence to be determined is in a court of law."

First Minister Mr Salmond added: "Mr Megrahi's death ends one chapter of the Lockerbie case but it does not close the book.

"However, all information that comes forward will confirm that the decisions of this administration have been in accordance with the due process of law."

Mr Salmond said Megrahi's death would end the conspiracy theories that suggested his illness was somehow manufactured.

He also emphasised that the Lockerbie case was still a live investigation, adding that "Scotland's criminal justice authorities have made clear that they will rigorously pursue any new lines of inquiry".

Three weeks ago, Frank Mulholland, the Lord Advocate, was in Tripoli with Robert Mueller, director of America's FBI, to discuss with the Libyan authorities the investigation into the bombing of Pan Am flight 103.

Mr Mulholland had earlier met Mr Mueller and Eric Holder, the US Attorney General, in Washington to discuss ways of stepping up officials' inquiries in Libya. At the time, the Lord Advocate noted that he wanted to "take advantage of the opportunity that has opened up with the fall of Gaddafi".

Last night, there were renewed calls for pressure to be exerted on Tripoli to get to the full truth about Lockerbie.

Richard Ottaway, the Conservative chairman of the Commons Foreign Affairs Committee, told The Herald: "Megrahi should never have been released in the first place. I suspect there is more to this story than we are aware of.

"I would encourage the UK Government to request further

information from the new Libyan Government about Lockerbie as well as the death of WPC Yvonne Fletcher, who was shot outside the Libyan Embassy in London in 1984."

He added: "In the chaos of the fall of Gaddafi a lot of information may have been destroyed or lost. It's possible we may never know the truth."

David Mundell, the Scotland Office Minister who is also the MP for Lockerbie, said: "There won't be closure for the bereaved or for others caught up in this tragedy until there are a lot more answers. There are obviously those who have information about the bombing who have not come forward.

"For the sake of the victims in particular, I hope anyone who does have information will come forward and complete the picture."

In Washington, the White House made clear the Libyan's death did not end the quest for justice.

"Megrahi's death concludes an unfortunate chapter following his release from prison in 2009 on medical grounds – a move we strongly opposed," said Tommy Vietor, the White House National Security Council spokesman.

"We want to see justice for the victims of the Lockerbie bombing and their families. We will continue working with our new partners in Libya toward a full accounting of Gaddafi's horrific acts."

David Ben-Ayreah, a spokesman for some of the British families of Lockerbie victims, claimed he had been told a week ago by sources in Tripoli that Megrahi had been slipping in and out of deep comas and that the secondary tumours had affected his abdomen and lower chest.

"As someone who attended the trial, I have never taken the view that Megrahi was guilty. Megrahi is the 271st victim of Lockerbie," he said.

Jim Swire, whose daughter Flora was another Lockerbie victim, described his death as "a very sad event", claiming fresh evidence would prove the Libyan was innocent.

However, Susan Cohen, whose 20-year-old daughter Theodora was killed in the bombing, said she hoped Megrahi had died "a painful, horrible death".

Speaking from her home in New Jersey, Mrs Cohen, 74, added: "I feel no pity for Megrahi. I believe he should have died a lot sooner. He should have been tried in the States and given the death penalty."