The Lockerbie bomber is at the center of a fresh row after it emerged he is taking a cancer drug that could keep him alive for five more years, The Sun reported.

Terminally ill Abdelbaset Ali al-Megrahi was prescribed chemotherapy treatment Taxotere after returning to Libya.

But on Sunday it was reported he wasn't given the drug while he was in Greenock prison in Scotland - amid claims he could have been kept behind bars if he had taken the medication.

Opposition justice spokesman Bill Aitken has demanded answers from Justice Secretary Kenny MacAskill.

He said: "Was the existence of a drug which is reportedly now extending the life of the Lockerbie bomber included in any of the reports Kenny MacAskill read before making the decision to release him?

SLIDESHOW: Lockerbie Bomber Abdel Baset al-Megrahi

"Alex Salmond's government is still refusing to publish the independent advice upon which they based their decision."

Megrahi - sentenced to life for the 1988 jet bombing that killed 270 people - was freed on compassionate grounds seven months ago and returned home to Libya.

On Sunday, it emerged the prostate cancer sufferer's condition has now stabilized.

A source close to the 57-year-old said: "After his treatments, he can be unwell for two or three days but then enjoys a period when he's quite well."

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