ROME (AP) - Hundreds of police raided a small town in southern Italy on Thursday and arrested more than 30 suspected members of organized crime clans believed to be involved in a feud that killed six Italians in Germany earlier this month.

Most of the arrests were in San Luca, the town where the two rival clans of the 'ndrangheta, the local version of the Sicilian Mafia, are based. Three suspects were found hiding in an underground bunker in the center of town, officials said.

The killings on Aug. 15 after a birthday party at an Italian restaurant in downtown Duisburg were seen as a family vendetta and the latest chapter of the long-standing feud between the San Luca clans.

The arrest operation Thursday, which involved some 300 police forces, did not target those suspected of direct involvement in the killings. But authorities put 32 suspects behind the bars, possibly averting the risk of further violence, said Renato Cortese, a top police official in the regional capital of Reggio Calabria.

"Presumably, there was going to be a reaction given that these two clans hate each other so much," Cortese said. However, authorities had no indication of immediate plans to avenge the Germany shooting, he said.

Interior Minister Giuliano Amato said the arrests were "a strong and necessary response by the state to break the Mafia feud between rival clans."

Forty-four people were targeted in the arrest warrants issued by Italian authorities as part of an investigation that started long before the Aug. 15 killings in Germany. About a dozen suspects are still on the run.

German and Italian authorities were conducting a separate investigation to find the killers of the six men, aged 16 to 38, police said.

Italian media reported that among those apprehended were the brothers of two of the victims in Germany, as well top bosses of both clans. While most suspects were in San Luca, some were arrested in a town near Rome.

Charges included Mafia association, murder and arms trafficking, authorities said.

San Luca, in the Calabria region that makes the toe of boot-shaped Italy, is a power base of the 'ndrangheta. Authorities say the crime syndicate has eclipsed the Sicilian Mafia in power and reach, thanks to its control of Europe's lucrative cocaine market. The feud between the two clans started in 1991, authorities have said.

Investigators from Germany and Italy met in Reggio Calabria on Thursday to review progress in the joint investigation and share information.