The clashes echoed the violence in neighboring France, where tens of thousands of people took to the streets on Saturday in some of the country's most violent protests in years.
Italian Police fired tear gas on Saturday after coming under attack from protesters throwing stones in the square in front of Milan's Gothic cathedral, Italian media reported, while there were also clashes in the city of Bologna following protests over the cost of living.
Police in Bologna used a water cannon to try to disperse crowds and made seven arrests after the protest became violent, the ANSA news agency reported.
'Demonstrating is a right, turning cities into battlegrounds is not'
Italian Prime Minister Giorgia Meloni, facing an election next year, condemned the violence.
"Demonstrating is a right. Turning our cities into battlegrounds is not," she said on X/Twitter.
In Milan, police in riot gear also tried to clear hooded protesters from the Galleria Vittorio Emanuele II, the luxury shopping arcade on one side of the cathedral square, as groups broke away from the cost-of-living protest.
Shops pulled down their shutters and tourists fled the central area. The central Duomo (Cathedral) metro station was closed during the clashes in which several people were reported injured, and arrests were made, according to Italian media reports.
The clashes echoed the violence in neighboring France, where tens of thousands of people, angered by rising costs and declining public services, took to the streets on Saturday in some of the country's most violent protests in years.