Congress should investigate whether a lucrative oil contract might have played a role in the release of the only man convicted in the 1988 Lockerbie bombing, a New Jersey senator said Wednesday.

Democratic Sen. Frank Lautenberg said the congressional panel "must expose the truth" and "uncover whether justice took a back seat to commercial interests."

On Aug. 20, Scottish authorities released from prison Abdel Baset al-Megrahi, who is dying from prostate cancer, on compassionate grounds. At the time, Scottish officials said doctors had determined he had less than three months to live.

Al-Megrahi, a former Libyan intelligence agent, served eight years of a life sentence for his role in the bombing of Pan Am Flight 103, which killed all 259 people on board and 11 people on the ground.

His release and warm homecoming in Libya sparked an international uproar, including rebukes from victims' families, President Barack Obama and FBI director Robert Mueller.

In London, The Sunday Times has reported that the British government decided that releasing the Lockerbie bomber would be in the overwhelming interests of the United Kingdom, as a major oil deal between Libya and BP was being negotiated.

Prime Minister Gordon Brown has denied that he gave any assurances to Libya's leaders that the bomber would be freed in exchange for oil contracts.

Scotland also has denied that business interests had anything to do with allowing al-Megrahi to leave prison and argue that compassionate release is a standard part of Scottish justice for dying prisoners.

Lautenberg called for a Senate investigation into the report in a letter to Sen. John Kerry, D-Mass., chairman of the Senate Foreign Relations Committee, and Sen. Richard Lugar, R-Ind., the panel's ranking member.

Kerry spokesman Frederick Jones said the senator opposed the release of al-Megrahi and the committee was planning to hold a hearing on U.S. relations with Libya.

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