Italian police have fired tear gas and water cannon at protesters who threw firecrackers, smoke bombs and bottles at them near a Winter Olympics venue.
Officers in riot gear and with shields confronted about 100 protesters, some of whom wore hoods and scarves to cover their faces, after they broke away from a main demonstration and appeared to be trying to reach the Santagiulia Olympic ice hockey rink.
A group of protesters also set off smoke bombs and firecrackers about half a mile (800 metres) from the Olympic Village, where around 1,500 athletes are staying.
Six people were arrested during the altercation, according to police sources.
The main demonstration saw an estimated 10,000 people taking to the streets of Milan on Saturday, on the first full day of the Winter Olympics, to protest against the environmental, economic and social impact of the Games.
Read more: Follow all the updates from the Winter Olympics in Italy
'Serious sabotage' on the rails
Meanwhile, the train network in northern Italy was hit by an act of "serious sabotage", according to the country's Ministry of Transport.
Police reported three acts of sabotage at three different locations, leading to passenger delays of up to two-and-a-half hours.
Rail infrastructure near Bologna was damaged on Saturday, causing the city's high-speed station to temporarily close, as train journeys were disrupted on the first full day of the Winter Olympics.
A cabin, housing a track switch, was set on fire in an early-morning attack near Pesaro, on the Adriatic coast.
Several hours later, electrical cables used to detect train speeds were found severed in Bologna, while a rudimentary explosive device was discovered by a track at a nearby location.
Nobody has claimed responsibility for the incidents, which appeared to have been coordinated, a police spokeswoman said.
Deputy prime minister Matteo Salvini, who heads up the transport ministry, said of the attacks: "These actions of unprecedented seriousness do not in any way tarnish Italy's image in the world, an image that the games will make even more compelling and positive."
Olympic infrastructure projects criticised
The march was organised by grassroots unions, housing-rights groups and social centre community activists.
Protesters carried cardboard cutouts of trees to represent the trees that were felled to build the new bobsled run in Cortina for the Olympics, arguing that infrastructure projects like this have damaged the environment in mountain communities.
"They bypassed the laws that usually are needed for major infrastructure projects, citing urgency for the Games," one protester said, adding that he was concerned that the private company organising the event would eventually pass on debt to Italian taxpayers.
The International Olympic Committee argues that the Games largely use existing facilities, making them more sustainable.
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Police brought the splinter group of violent protesters under control before the main demonstration finished, according to Italian news agency ANSA.
'ICE out' signs
Some protesters said they were opposed to the deployment of US immigration and customs enforcement (ICE) agents to Italy to provide security to the US delegation of athletes, following previous protests in the buildup to the Games.
US Homeland Security Investigations, an ICE unit that focuses on cross-border crimes, often sends officers to events abroad like the Olympics to help with security.
The ICE unit used to crack down on immigration in the US is known as Enforcement and Removal Operations, and there is no indication its officers have been deployed to Italy.
(c) Sky News 2026: Italian police fire tear gas at protesters near Olympics venue
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