Monday's operation dubbed "Pressing II" was the second phase of a "vast" probe that began in 2008. The first phase of the invesigation, "Pressing I" led to the arrests on 18 March 2010 of five people suspected of association with the Naples mafia, or Camorra, and of extortion, police said.
Among the five people arrested was a "professional" in the Modena area who had no criminal record, police said. The extent of the mafia's links to businesses, especially in Italy's more prosperous, industrial north, is continuing to emerge, according to anti-mafia prosecutors.
The Camorra from the area in and around Naples, the Sicilian Cosa Nostra and the 'Ndrangheta from the Calabria region, are Italy's largest and most powerful mafia organisations.
Annual earnings by the Italian mafia are estimated to total more than 75 billion euros from extortion and loan sharking alone Other activities include money laundering, drugs and arms trafficking and prostitution.