The suspects were arrested throughout the country on charges of conspiracy, collusion, illegal gambling and betting, extortion, threats of violence, computer fraud, money laundering and fraud, Italy's ANSA news agency reported.
Police also seized more than $587 million worth of assets that included bank accounts, properties, businesses and automobiles.
Also Thursday, Italian police arrested Alessandro Mazzullo, 29, an alleged member of the Calabrian 'Ndrangheta mafia in Rome, ANSA said.
Mazzullo has been on the run since he fled an arrest warrant for fraud in January.
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