The arrests were coordinated by DDA anti-mafia investigators.
A preliminary investigations judge issued 15 arrest warrants, including for a suspect who is wanted by police, on charges of usury and extortion.
The victims identified by police are two men residing in the Poggioreale district of Naples who contracted debts with interest rates often exceeding 100 per cent a month, sources said.
Eight people were detained in prison while the remaining suspects were placed under house arrest.
Carabinieri police are looking for the 15th suspect.
ANSA
