Italian Prime Minister Giorgia Meloni has condemned anti-Olympics protesters as "enemies of Italy" after violence on the fringes of a demonstration in Milan on Saturday night and sabotage attacks on the national rail network.
The incidents happened on the first full day of competition in the Winter Games that Milan, Italy's financial capital, is hosting with the Alpine town of Cortina d'Ampezzo.
Meloni praised the thousands of Italians who she said were working to make the Games run smoothly and present a positive face of Italy.
"Then there are those who are enemies of Italy and Italians, demonstrating 'against the Olympics' and ensuring that these images are broadcast on television screens around the world. After others cut the railway cables to prevent trains from departing," she wrote on Instagram on Sunday.
A group of around 100 protesters threw firecrackers, smoke bombs and bottles at police after breaking away from the main body of a demonstration in Milan.
An estimated 10,000 people had taken to the city's streets in a protest over housing costs and environmental concerns linked to the Games.
Police used water cannon to restore order and detained six people.
Also on Saturday, authorities said saboteurs had damaged rail infrastructure near the northern Italian city of Bologna, disrupting train journeys.
Police reported three separate incidents at different locations, which caused delays of up to 2-1/2 hours for high-speed, Intercity and regional services.
No one has claimed responsibility for the damage.
"Once again, solidarity with the police, the city of Milan, and all those who will see their work undermined by these gangs of criminals," added Meloni, who heads a right-wing coalition.
The Italian police have been given new arrest powers after violence last weekend at a protest by the hard-left in the city of Turin, in which more than 100 police officers were injured.

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