The head of the FBI and Scotland's top prosecutor visited Libya to help pave the way for further investigations into the 1988 Lockerbie plane bombing, Sky News reports.

FBI Director Robert Mueller and Lord Advocate Frank Mulholland held a meeting with Libyan Prime Minister Abdurahim el Keib in Tripoli to discuss an ongoing investigation into the bombing, the news station reports.

Abdel Baset al Megrahi is the only individual ever convicted in the bombing that killed 270 people. Scotland authorities have reportedly maintained the belief that the bombing was carried out by a number of individuals in an act of state-sponsored terrorism.

"The Libyan authorities confirmed that they fully understood the importance of dealing with the tragic issues left behind by Colonel Qaddafi and his regime, both in Libya and overseas," a spokesman for Scotland's Crown Office and Prosecutor Fiscal Service told Sky News.

"The Lord Advocate expressed his desire to the Libyan Prime Minister that there will be a positive response to his recent request for cooperation and the International Letter of Request," he said.

There was no attempt to visit al Megrahi, who was released from a Scottish prison in 2009 on compassionate grounds, during the visit.

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