Italy’s financial police say they have broken up a smuggling ring selling cheap Libyan diesel at service stations in Sicily and elsewhere in Europe.

The smugglers were allegedly obtaining fuel destined for ships from a refinery operated by Libya's National Oil Corporation at Zawiyah, about 40km (25 miles) west of Tripoli, the AFP news agency reports.

According to the Italian media, during a year-long investigation, the police documented more than 30 journeys in which fuel worth 30m euros ($35m, £27m) was imported illegally.

Italy's La Sicilia paper says six arrest warrants have been issued - for two Maltese, two Libyans and four Italians. According to AFP, the warrants include one for the head of the Italian company implicated in the alleged fraud and an Italian go-between suspected of having mafia links.

A prosecutor in the Sicilian city of Catania, Carmelo Zuccaro, said he could not rule out the proceeds had gone to Islamic State militants, but there was no evidence for this, La Sicilia reports.