Italian police have arrested 11 people from a gang which stole medicines and money worth more than one million euros from drug distribution firms and insurance agencies.

The sweep in the Sicilian capital Palermo targeted the Banda della Molara gang, which staged 14 "lightning" attacks with fire arms between 2006 and 2008, the statement said.

The medicines were stolen from transport trucks in meticulously planned operations and then sold to pharmacies at half price.

"It was a parallel market potentially hazardous for clients as they were stocked in warehouses ... lacking in hygiene standards and the necessary temperature controls," it said.

The gang worked with the go-ahead of the Sicilian mafia, with whom they shared a part of the profits.