About 20 Nigerians and Ghanaians have been arrested on suspicion of exploiting illegal migrants for prostitution, say Italian police.
Reports say the ongoing operation is being directed by the anti-mafia prosecutor's office in the city of Naples.
They are being charged with mafia association, illegal migration, slavery and exploiting prostitution.
Benedetto Cataldi of the BBC's Monitoring Unit says this is the first time that the very serious charge of running a mafia operation has been extended to sub-Saharan Africans.
The arrests are said to have taken place in a number of Italian cities, including Naples itself, Rome, and Turin.
If found guilty they could face at least 15 years in jail each.
Life of fear
The Italian Government has in recent times been battling to beat organised crimes including rampant prostitution, extortion and exploitation.
Thousands of people from both eastern Europe, north Africa, Ethiopia and West African are estimated to be smuggled through Italy's extensive coastline every year, on the understanding of legitimate work.
But once in Italy, their passports are taken by pimps or godfather and godmother like figures who force them into prostitution.
The immigrants, usually unable to speak the language, are terrified and forced to move from city to city not knowing where they are.
It is estimated that there could be more than 40,000 foreign prostitutes on the streets of Italy - and the numbers are increasing.