Italian police have arrested the new head of the Sicilian mafia and 45 other alleged mobsters in a powerful blow to organised crime on the Mediterranean island, Deputy Prime Minister Luigi Di Maio said.

The previous boss of bosses, Salvatore ‘Toto’ Riina, died in prison last year after spending almost a quarter of century behind bars for ordering dozens of murders, including those of two of Italy’s most famous anti-mob magistrates.

Police said among those arrested on Tuesday was Settimo Mineo, head of the local mafia families in the Sicilian capital of Palermo.

Officials said he had recently been named the overall head of the island’s mafia, known as Cosa Nostra (Our Thing).

“The arrests … represent one of the biggest blows inflicted on the mafia by the state. Mineo had been elected ‘heir’ of Toto Riina after his death. There is no more room for this type of scum in Italy,” Mr Di Maio wrote on Instagram.

It’s believed police arrested 80-year-old jeweller Mineo just before he was due to be officially anointed at a reconvened Mafia Commission or Cupola, police said.

Police are due to release more details about their operation later on Tuesday.

It follows 68 arrests of organised crime families by Italy’s National Anti-Mafia Directorate (DNA) across Italy in mid-November.

That operation was conducted with assistance from the European Union’s judicial agency Eurojust and police from Britain, the Netherlands, Serbia and Switzerland.

Those arrested were allegedly members of the country’s three major crime syndicates: Sicily’s Cosa Nostra, Calabria’s ‘Ndrangheta and Apulia’s Sacra Corona Unita (SCU).

About 800 officers were involved in the raids, which were prompted by information given by a Sicilian mobster.

-with AAP