The Soufan Group said in a report — titled Beyond The Caliphate: Foreign Fighters and the Threat of Returnees — released overnight that the potential return of unknown numbers of foreign fighters represents a huge challenge for law enforcement agencies.The New York-based group, which closely follows militant factions, said is remains to be seen what the displaced fighters will do once returned and whether or not they will stage homegrown attacks.But the Soufan group says it is inevitable that some will want to continue waging violent jihad.
Libya, which sits at the nexus of trafficking routes from sub-Saharan Africa, could be examined by the International Criminal Court but the body has no jurisdiction over Isis territories where crimes are taking place in Iraq and Syria.
Migrants have toldof their horrific experiences being detained, ransomed and forced into labour in the country, which remains at war six years after the UK led a military intervention against Muammar Gaddafi.
Research by the UN’s International Organisation of Migration showed that 91 per cent of those reaching Italy on migrant boats had experienced human trafficking in Libya, including some approached with offers of arranged marriage or organ sales.
No evidence of Isis systematically using the refugee crisis has been found but one smuggler confessed that he received a call from a militant offering money in exchange for shipping 25 people in a boat to Europe last year.
Of the Australians listed in the report, some 100 are believed to be still there while at least 40 have returned — at least 95 are believed to be women and children.
Thousands of IS fighters have been killed on the battlefield as Syrian and Iraqi forces have retaken nearly all the territory once held by the group, and many of those returning could be disenchanted with extremism.
It said more than 40,000 foreigners flocked to join IS from more than 110 countries, both before and after the extremists declared a caliphate in June 2014.
It said they included more than 8,700 from the former Soviet Union, 5,718 from western Europe, 439 from North America, and more than 165 from Australia.
The terrorist group’s genocide against the Yazidis of Sinjar saw thousands of women and girls abducted as sex slaves to be passed around and sold among fighters.