More than 100 people have been arrested in anti-Mafia operations across Italy, Europe and Latin America, police say.
Police said suspects were believed to be involved in drugs trafficking
Naples police said they had detained at least 90 people in Italy and elsewhere, suspected of running an international drugs trafficking ring.
A second operation targeted a Mafia network with ties to Italy's southern Calabria region, with most arrests taking place in Milan, in the north.
Those held are suspected of involvement in drugs and arms trafficking.
Naples prosecutors said further arrests had been made in Ecuador, Spain, France, Colombia, the Netherlands, Germany and Bulgaria.
Italy's Prime Minister Romano Prodi last month described organised crime as the biggest hurdle confronting southern Italy's economic growth.
A recent Mafia turf war in Naples led to calls for the army to be deployed.
Some 2,500 people have died in violence blamed on Italy's three main Mafia groups in the past 10 years.