Police have arrested a leader of Inter Milan's hardcore "ultras" fan group following the death of a supporter during clashes with visiting Napoli fans last week.
The ANSA news agency reports that Marco Piovella, the arrested fan, is being charged with homicide.
Investigators believe that Daniele Belardinelli, the 35-year-old fan who died, may have been fatally struck by a van or SUV during the clashes outside the San Siro stadium.
Investigators believe that the Inter fans instigated the clashes with a pre-planned assault on a large group of Napoli's hardcore ultras, who avoided police detection by arriving in minivans.
At least four Napoli fans were injured in the clashes -- where bars, knives and other weapons were reportedly used -- and three Inter supporters were already arrested.
The Dec. 26 match was also marred by racist chants aimed at Napoli defender Kalidou Koulibaly.
Inter has been ordered to play its next two home matches in an empty stadium, plus a third home game with a partial closure of the San Siro.
Inter fans were also barred from traveling to a match at Empoli last Saturday.