GETTY Some of the terrorists behind the Lockerbie bombing are now fighting with ISIS

FREE now SUBSCRIBE Invalid email Make the most of your money by signing up to our newsletter fornow We will use your email address only for sending you newsletters. Please see our Privacy Notice for details of your data protection rights.

Robert Baer said it was even possible that the failure to bring all of those responsible for the December 1988 atrocity to justice had contributed to the rise of IS. The former Middle East case officer was speaking after Kenny MacAskill accused Iran, Syria and the Popular Front for the Liberation of Palestine-General Command (PFLP-GC) of plotting Lockerbie. In his new book, the ex-SNP Justice Secretary says the bombing was ordered by Iran and that Libya "picked up the pieces" after German police raids broke up a PFLP-GC cell. Two Libyans, Abdelbaset Megrahi and Lameen Fhima, were eventually put on trial and Megrahi was convicted, before being released with terminal cancer almost seven years ago.

Mr Baer, who worked for US intelligence from 1976 to 1997, said MacAskill had shown "enormous courage" in "pointing out the truth" about Lockerbie. He backed calls for Scottish and US prosecutors to pursue PFLP-GC leader Ahmed Jibril, who the Sunday Express recently traced to the Syrian capital Damascus. However, he added: "If they handed over Jibril and he talked he would implicate the Iranians and Syria is effectively run by Iran so it would just never happen." Although Jibril and the PFLP-GC are now fighting with the Syrian regime against IS, Mr Baer said many former members had converted to Islamic extremism. "Some of the earlier bombers have washed up with the Islamic State," he said.

NC Robert Baer said it was even possible the terrorists had contributed to the rise of ISIS

Some of the earlier bombers have washed up with the Islamic State Robert Baer

"The acetone peroxide or TATP bombs, which is what the people in Paris blew themselves up with, was originally designed to put in the walls of a suitcase and bring down an airplane. "Abu Ibrahim [the leader of the May 15 group, another offshoot of the PFLP and an initial Lockerbie suspect] has ended up with IS. He was in a safe house Baghdad in 2003 but he escaped just before we got to him." Just weeks before Lockerbie, a German anti-terror operation codenamed Autumn Leaves raided a PFLP-GC cell led by Hafez Dalkamoni and including bomb-maker Marwan Khreesat and second-in-command Abdel Fattah Ghadanfar. Fourteen members, including Khreesat, were released almost immediately, while Dalkamoni and Ghadanfar were jailed for several years before being deported to Syria.

The fight against ISIS Fri, November 18, 2016 The battle against ISIS militants (also abbreviated as Daesh, ISIL, IS and Islamic State) continues in the Middle East. Play slideshow Getty 1 of 183 Forces battle against ISIS

The whereabouts of Dalkamoni and Ghadanfar is currently unknown, although Khreesat - who has been described as a double or even a triple agent - is living in Jordan. Mr Baer said it was "almost certain" that terrorist bomb-makers from the 1980s had gone on to train IS fighters or become fully-fledged members of the group. He said: "Ibrahim, Khreesat, Dalkamoni. A bunch of them have their signatures in the IS bombings in Fallujah and Baghdad." He added: "The PFLP-GC is still a socialist, almost Communist organisation but big parts of it have switched to Islam. Dalkamoni was in jail in Germany during the First Intifada and he felt terrible he wasn't part of it. He was sitting it out and he wasn't participating in this war against Israel. He had a road to Damascus conversion."

NC

GETTY The ex-SNP Justice Secretary says the bombing was ordered by Iran