The US Justice Department unsealed new charges against a third Libyan man in the 1988 bombing of a Pan Am jet over Lockerbie, Scotland, that killed 270 people, including 190 Americans.
The suspect, Abu Agila Mohammad Masud, is a Libyan intelligence official and is charged with two criminal counts related to the bombing.
Masud is in custody in Libya and Barr said he believes the Libyan government will let him be extradited to the US to be tried.
Masud is accused of building the bomb that destroyed Flight 103 and working with two other Libyan Intelligence Agency operatives – Abdel Basset Ali al-Megrahi and Lamen Khalifa Fhimah – to carry out the plot.