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Milan's authorities said they would start checking people's documents in the city's most racially diverse neighbourhoods in order to root out illegal immigrants.
Milan's deputy mayor, Riccardo De Corato, said officials would go from building to building in areas where immigrants live. Half of the 46 immigrants picked up by police on Saturday night had been found to be in Italy illegally, he said.
The Northern League, a right-wing, anti-immigrant party within prime minister Silvio Berlusconi's centre-right coalition, called for the immigrants responsible for the violence to be expelled. One member of the League, MEP Matteo Salvini, called for "expulsions house by house, floor by floor".
The outbreak of violence between the two immigrant groups shocked Italians, many of whom have struggled to come to terms with the relatively recent advent of a multi-ethnic society. "It's like something out of Los Angeles, with the gang fights between the Bloods and the Crips," commented La Stampa on its front page.
It was the second violent episode involving immigrants this year, after riots broke out in the southern town of Rosarno, in Calabria, when African agricultural workers burned cars and broke store windows to protest against attacks by local white youths.
The Telegraph