The Popular Front for the Liberation of Palestine – General Command ( PFLP-GC ) was the first suspect , in light of a threat it issued against U.S. and Israeli interests before the bombing . The state of Iran was also in the frame very early , with its motive thought to be revenge for the July 1988 shooting down of Iran Air Flight 655 by . This theory was later reinforced by Abolghasem Mesbahi , former head of Iranian intelligence operations in Europe , who stated after defecting to Germany that Iran had asked Libya and Abu Nidal , a Palestinian guerrilla leader , to carry out the attack on Pan Am 103 . In his 1994 film '' The Maltese Double Cross '' , Allan Francovich suggested that rogue CIA agents were implicated in a plot that involved them turning a blind eye to a drug running operation in return for intelligence . Evidence presented at Megrahi 's trial , together with concerns about the reliability of his conviction , spawned a theory that Libya was framed . Abu Nidal allegedly confessed to the bombing before his death , thereby triggering another theory , while Joe Vialls put forward his own explanation that relied on the bomb being detonated remotely . Finally , in December 2013 , Patrick Haseldine suggested that the bombing was an assassination by South Africa 's apartheid government of United Nations Commissioner for Namibia , Bernt Carlsson
Iran Air Flight 655
Iran Air Flight 655
Pan Am Flight 103 conspiracy theories