US politicians are calling for the new Libyan authorities to extradite the only man convicted for the December 1988 bombing of Pan Am flight 103, which killed 270 people when it exploded over the Scottish town of Lockerbie.
Abdelbaset Ali Mohmet al-Megrahi, who has terminal cancer, was said to have only three months to live when he was released from a Scottish jail on compassionate grounds on August 20, 2009.
Megrahi then made his first public appearance in nearly two years in July at a meeting supporting embattled Libyan leader Muammar Gaddafi.
US Republican presidential hopeful Mitt Romney on Monday called on the new Libya authorities "to arrest and extradite the mastermind behind the bombing of Pan Am 103 ... so justice can finally be done," he said in a statement.
New Jersey Senator Robert Menendez in turn reiterated earlier calls for Megrahi's extradition to the United States.
Libya's transitional authorities "should extradite al-Megrahi to the United States to answer for the bombing of Pan Am flight 103," Menendez told Foreign Policy magazine. "There would be no better signal to the world that a new Libya believes in justice and has every intention to adhere to international law."
Most of those killed on the fateful 1988 London to New York flight were Americans -- and New York senators Charles Schumer and Kirsten Gillibrand on Monday called for Megrahi to be jailed again.
"As a transitional government takes hold in Libya, it should seek to undo the injustice of al-Megrahi's release by returning him to the jail cell where he belongs," Schumer said in a statement.
Megrahi's 2009 release "was a total miscarriage of justice," Gillibrand said in a statement. "Seeing him participate in good health at a pro-Gaddafi rally recently was another slap in the face not just for the families of the Lockerbie victims, but for all Americans and all nations of the world who are committed to bringing terrorists to justice."
Libya's transitional government "should immediately seek justice and hold this terrorist accountable by sending him back to prison," she said.
British Prime Minister David Cameron has criticized al-Megrahi's release as a "terrible mistake," and Deputy Prime Minister Nick Clegg has said he would like to see him "back in jail behind bars."
However Megrahi "was convicted in a Scottish court under Scottish law," a Foreign Office spokesman told CNN. "He could be returned under the terms of his release, but this is matter for the relevant judicial authorities and it is not something that the British government can interfere with," the spokesman told CNN.
Separately, the United States has no extradition treaty with Libya, and a Transitional National Council representative said that any decision about Megrahi's future would have to wait until a new government is elected, which could take up to two years, the Los Angeles Times reported.