The alleged gang leader's suspected backing for radical Islamism was uncovered during an investigation into the group's provision of false job contracts from local textile factories to enable illegal immigrants from North Africa to obtain work permits, a statement from the ROS police special operations unit said.

Arrest warrants have been issued for eight suspects. They included the Tunisian, who was said to have become radicalized in the last year and to have praised the recent terror attacks on Paris on social media.

Further details of the operation were to be released at a press conference later Friday.

It came against a backdrop of mounting concern about the possibility of Italy being hit by “lone wolf” terror attacks of the kind seen in neighbouring France, Belgium and Britain.

Recent weeks have seen a string of suspected Islamists expelled from the country on the order of Interior Minister Angelino Alfano.

Most of the orders, which are not subject to appeal within Italy, have been issued on the basis of the suspects having expressed support for radical Islamist ideas rather than any evidence of them actively planning to act on them.

Among those expelled was Aftab Farook, a young Pakistani who previously captained Italy's under-19 cricket team.

Farook's family say his expulsion breached his rights and are planning to challenge it via the European Court of Human Rights.

Italy's centre-left government meanwhile is considering appointing a commission of experts to draw up proposals for combating radicalisation in the country's Muslim population.

The panel, proposed by junior security minister Marco Minniti, would report directly to Prime Minister Matteo Renzi.

It would notably be tasked with setting guidelines for the profiling of potential suspects and parameters for monitoring mosques, workplaces and schools subject to possible infiltration by radical elements, La Stampa reported.