ISIS has turned its attention to establish a power base among African militants in Chad, Nigeria, Mali and Sudan to build its burgeoning army in Libya.
A number of cities in Libya have already been overrun by ISIS, including Sirte, the home city of former leader Muammar Gaddafi.
Several ISIS communities in the war-torn state have established Sharia courts as well as government offices and routine public beheadings.
The radical terror group, which also goes by the name of Daesh, is said to be offering £700 ($1,000) bribes to thousands of mercenaries from surrounding African states, to build on its success across Syria and Iraq.
There are an estimated 3,000 fighters already based in Sirte, 70 per cent of whom are believed to be non-Libyan.
Britain is among a number of Western countries desperately trying to convince Libya to accept an offer of a thousand UK troops to combat the rising tide of extremism.
The US is leading the efforts to stop Sirte becoming the Libyan equivalent of the ISIS stronghold of Raqqa in Syria.
There are growing concerns that ISIS could use Libya as a launchpad for attacks in Europe, even smuggling fighters across the Mediterranean disguised as refugees.
Only 200 miles separates the coastal African city and continental Europe.
Libyan officials admit they are almost powerless to stop the flood of foreign fighters but remain wary of allowing Western boots on the ground.
Both Downing Street and the Pentagon have offered the Libyan government up to 1,000 British troops and 5,000 Italian troops in a training role tackle the extremists.
Colonel Muncif al Walda, a senior police officer in the nearby city of Misrata, is among the Libyans arguing for Western intervention.
He said a Paris-style terror attack planned by ISIS in Libya could be carried out by terrorists disuised as migrants, Express reported.
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