Among those arrested in coordinated actions in the Calabria region of southern Italy and in northern Italy were the wife and sister of mob boss Francesco Vottari.
None of the suspects arrested on Friday are accused of participating in the brutal shootings on August 15 of six men, aged 16 to 38, in front of an Italian restaurant in Duisburg, a city in the German region of North Rhine-Westphalia.
But those arrested are accused of belonging to the mafia and trafficking weapons and explosives in the southern Italian town of San Luca, a stronghold of the Italian organized crime confederation 'Ndrangheta, and in Germany, according to a report in the Italian newspaper Corriere della Sera.
The group's German dealings were said to have taken place mostly in Duisburg and the neighboring city of Kaarst.
Five of the men shot in Duisburg were from San Luca. The motive for the shooting is believed to have been revenge: the wife of a rival crime clan leader had been shot, and her son injured, around Christmas 2006 in San Luca.