In Trapani, police seized hundreds of thousands of dollars in assets belonging to Matteo Messina Denaro, who allegedly took control of Cosa Nostra after the 2006 arrest of Bernardo Provenzano, Italy's ANSA news agency reported.
Police said all of the assets seized from Denaro, which included olive oil businesses, cars and bank accounts, were in the name of his sister Anna and her husband, Vincenzo Panicola, who is detained on mafia charges.
Denaro has been in hiding for several years.
In Salerno, police seized $1.3 million in assets from Piero Lazzaro Cavallo, a suspected member of the Neapolitan Camorra, ANSA said.
Cavallo allegedly invested profits from video-poker and other illegal-gambling into legitimate businesses, police said.
Meanwhile, in Rome, a 'Ndrangheta boss Vincenzo Femia was shot and killed on the outskirts of the city Thursday night, police said.
Femia, who had been the head of the Calabrian mafia's branch in Rome for 20 years, was hit by at least nine bullets while sitting in his car, police said.