Police have arrested 12 hardcore Juventus "ultra" fan leaders for a series of accusations, including making illegal demands to the club to obtain more tickets.

Police say fans threatened to carry out racist chants during matches if they were not given more tickets than the number allotted. The investigation by Turin prosecutors is linked to alleged infiltration of the Calabrian 'ndrangheta crime mob into the "ultras" section at Allianz Stadium. Charges include criminal association, extortion, money laundering and violence.

The investigation was triggered by a charge from Juventus a year ago. The arrests come two years after the club was fined and ordered to play a match with one of the main sections of its stadium closed for selling tickets to "ultras" and encouraging scalping. Juventus president Andrea Agnelli was fined for the sales to "ultras," but his one-year ban was lifted by an Italian soccer federation appeals court in December, 2017.