TORONTO — Police said they arrested more than 400 people after a demonstration against the Group of 20 summit turned violent in downtown Toronto and braced for more possible trouble Sunday.
Police spokeswoman Michelle Murphy said 412 people had been arrested across the city after what she described as "quite a messy protest" on Saturday. They face charges ranging from mischief to assaulting police,
Saturday's protest started as a peaceful demonstration, but rapidly turned into a riot after groups of masked anarchists broke away from the main crowd, smashing store windows and banks and torching at least two police cars.
Smoke from the fires wafted up past the luxury downtown hotel where the world leaders were meeting, in a closed-off area protected by fences and ranks of scores of police in a security operation that cost Canada about $1 billion dollars.
Police hoped that any protests scheduled for Sunday, the final day of the meetings, would be peaceful, but were ready to respond. "If everything blows, as it did yesterday, we will react accordingly," Murphy said.
Police, who admitted they had at times lost control of the situation, used tear gas to control Saturday's crowd.
"What we saw yesterday … is a bunch of thugs that pretend to have a difference of opinion with policies and instead choose violence in order to express those so-called differences of opinion," Dimitri Soudas, spokesman for Canadian Prime Minister Stephen Harper, told a news conference.
"People do disagree on issues, leaders that meet all the time don't necessarily always see eye to all the time. But you don't see people burning up police cars and breaking windows."
By morning, Toronto, Canada's largest city, was calm.
Behind the Ontario legislature, where police made mass arrests on Saturday night, a solitary figure practiced tai chi on the grass in faint early morning sunshine while police on bicycles rode up and down in front of the building.
A number of store fronts and bank windows were boarded up elsewhere in the downtown core, and a worker was busy covering a big Starbucks sign with a black garbage bag for fear that Saturday's mayhem would be repeated.
Anti- G-20 groups have been demonstrating in Toronto leading up to the summit of rich and emerging economies, which follows a smaller meeting of Group of Eight industrial nations.