Italian police have launched a crackdown on suspected mafia mobsters, arresting around 100 people in overnight raids. The operation was nine months in the planning, and involved more than 1,200 officers, supported by helicopters. They seized clan chiefs and members of mafia families in Sicily and in Tuscany on the mainland. The suspects are accused of trying to re-form the Cosa Nostra, the Sicilian mafia organisation which was mortally wounded by the 2006 arrest of its then-chief Bernardo Provenzano. Police believe a current mafia leader called Matteo Messina Denaro is behind attempts to re-launch the Cosa Nostra. He has been competing for control of the Sicilian branch since Provenzano’s arrest, but escaped the overnight operation and remains at large.