The operation, which involved over 100 special agents, implicated mafia families in Vita and Salemi, two towns in western Sicily, a police statement said.
Authorities were set on the trail after 60 hectares (150 acres) of land in the region were sold for a price perceived to be too low.
“The real price of the land was far higher than the sale price… The difference, more than EUR200,000 ($246,700) was pocketed by members of Cosa Nostra,” said police, referring to the Sicilian organised crime group.
“Part of this money… was destined for the upkeep of fugitive Matteo Messina Denaro.”
Hunted by police since 1993, Messina Denaro, who turns 56 next month, is considered to be the successor of historic Cosa Nostra bosses Toto Riina and Bernardo Provenzano, both of whom died recently in prison.
A former Cosa Nostra hitman, Messina Denaro was sentenced in absentia to life in prison for multiple murders. He was known for his ruthlessness and reportedly boasted he could “fill a cemetery” with his victims.
The only known photo of him dates back to the beginning of the 1990s.
Over the last two decades Italian police have increased arrests and seizures within his entourage, in a bid to isolate the notorious boss, a strategy which has so far failed to bear fruit.
In 2015, police discovered that Messina Denaro had abandoned modern methods of communication and was executing orders to his men via traditional “pizzini“: small bits of paper containing encoded messages.
Last December, 200 police officers searched homes and businesses belonging to known allies of the mobster in an attempt to uncover spots where the fugitive could be hiding.