The Lockerbie bomber, Abdelbaset Ali al-Megrahi, should never have been released David Cameron said today.
Mr Cameron called on the public to remember the victims of the Lockerbie bombing, following reports that Megrahi had died today in Libya.
Abdelbaset Ali al-Megrahi was sentenced to life in prison for the 1988 bombing of a US airliner over the Scottish town which claimed 270 lives.
He was later diagnosed with terminal prostate cancer and died today in Libya - two years and nine months after his controversial release from jail on compassionate grounds.
Mr Cameron said: “I've always been clear he should never have been released from prison.
“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've had.”
The Prime Minister dismissed calls for an inquiry into Megrahi's conviction which the Libyan always contested.
“This has been thoroughly gone through,” he said.
“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.”
Megrahi was released from jail on August 20 2009 and sent back to Tripoli with an estimated three months to live.
The decision to free him by Scottish Justice Secretary Kenny MacAskill provoked an international storm.
In death, Megrahi continued to divide opinion.
The mother of a young aspiring actress killed in the atrocity said she hoped the convicted terrorist suffered a “painful, horrible” death, while a spokesman for some of his British victims said his death was “deeply regretted”.
Former Liberal Democrat leader and Scottish QC Sir Menzies Campbell said: “This brings to a satisfactory end a controversial series of events which began with the terrible and tragic loss of life over Lockerbie.
“The decision to release Mr Megrahi was ill-judged and undermined confidence in the Scottish legal system.
“Answers to many of the outstanding questions have died with Mr Megrahi.”
The bombing of Pan Am flight 103, travelling from London to New York four days before Christmas, killed all 259 people on board.
Eleven residents of the Dumfries and Galloway town also died after the plane crashed down on their homes in Britain's biggest terrorist atrocity.
After protracted international pressure, Megrahi was put on trial under Scots law at Camp Zeist in the Netherlands.
He was found guilty in 2001 of mass murder and was ordered to serve a minimum of 27 years behind bars.
Despite claims that he could not have worked alone, and the lingering suspicion by some that he was innocent, Megrahi was the only man ever brought to justice over the terrorist attack.
Mr MacAskill's decision to allow him to return home to die in Libya sparked international condemnation from some relatives of victims and politicians, who demanded he be returned to jail.
Scottish ministers have always insisted their decision was made in good faith, on compassionate grounds alone and followed the due process of Scots law.
But those who opposed the decision insisted Megrahi should not have been freed.
US families were among the most vocal critics of the decision, along with US president Barack Obama. US secretary of state Hillary Clinton branded the move “absolutely wrong”.
American fury was compounded by the hero's welcome Megrahi received in Tripoli upon his return.
Susan Cohen, whose daughter Theodora, 20, was on board Pan Am flight 103 bound for John F Kennedy airport, said she believed Megrahi should have received the death penalty.
Speaking from her home in Cape May Court House, New Jersey, Mrs Cohen, 74, said: “He died with his family around him. My daughter died a horrible death when she was 20 years old with her full life ahead of her. You call that justice?
“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. Watching him be released from prison was very painful for me.”
Mrs Cohen said questions still remain about how the bombing happened and who was involved in the crash which killed her daughter, a student who hoped to become an actress.
“I think this was to do with deals in the dust and it is despicable. We cannot let Megrahi's death stand in the way of the Scottish and American government finding out who else was involved in the bombings and the specifics of how it was done.
“I don't believe conspiracy theories that Megrahi was innocent.”
But David Ben-Ayreah, a spokesman for some of Megrahi's British victims, described Megrahi as the “271st victim of Lockerbie”.
“I was told seven days ago by very good sources in Tripoli that he was slipping in and out of quite deep comas, that the secondary tumours had affected his abdomen and lower chest, and that he had had three blood transfusions,” he said.
“His death is to be deeply regretted. As someone who attended the trial I have never taken the view that Megrahi was guilty.”
Martin Cadman, from Norfolk, whose son Bill died in the flight at the age of 32, said: “The only thing I am interested in is getting to the truth. The Americans know far more than they have said.”
Jim Swire, whose daughter Flora was killed in the bombing, said Megrahi's death was a “very sad event”.
Dr Swire, a member of the Justice for Megrahi (JFM) campaign, said he believed there was evidence yet to be released which would prove his innocence.
“It's a very sad event,” he told Sky News.
“Right up to the end he was determined - for his family's sake, he knew it was too late for him, but for his family's sake - how the verdict against him should be overturned.
“And also he wanted that for the sake of those relatives who had come to the conclusion after studying the evidence that he wasn't guilty, and I think that's going to happen.”
Scottish Labour leader Johann Lamont branded the decision to release Megrahi an “insult to the victims”.
“At this moment let me, on behalf of the people of Scotland, apologise to the families of all the victims of the Lockerbie bombing, for his early release,” he said.
Scottish Liberal Democrats leader Willie Rennie said: “Although this is an end to a chapter of one of the worst terrorist events in Scotland there should be no celebration that Abdelbaset al-Megrahi has died.
“Instead it should act as a spur to establish the facts including whether crucial forensic evidence was withheld from the trial.”
Megrahi had rarely been seen since his return to Tripoli, but he was spotted on Libyan television at what appeared to be a pro-government rally in July.
UK Foreign Secretary William Hague said the public appearance confirmed a “great mistake” was made in releasing him from jail.
Prior to Megrahi's death, reports suggested his prostate cancer had spread to his neck. Others said he had been kept alive with cancer drugs unavailable in the UK.
Consultant urologist professor Roger Kirby, founder and director of The Prostate Centre in London, said he believed that abiraterone was likely to have been responsible for Megrahi's prolonged life well beyond the three-month point.
Despite sparking international controversy, and a vote symbolically rejecting the decision in the Scottish Parliament, Megrahi's release from prison appeared to have had no effect on the SNP's fortunes.
The party, with Mr MacAskill, was returned to power at Holyrood in a landslide victory in May last year.
JFM, which represents victims' families who are sceptical over Megrahi's responsibility for the bombing, has called for the appeal against his conviction to be reopened.