TORONTO -- Police and protesters clashed near a makeshift detention centre in Toronto on Sunday, a day after a peaceful protest aimed at the G20 summit turned ugly in Canada's largest city.
Police fired rubber bullets into a crowd of about 150 anti-G20 demonstrators outside the downtown facility where arrested protesters were being held.
Many of the supporters outside the converted film studio, located on Eastern Ave. in the city's east end, banged on pots and pans and chanted "let them go" before police acted with force to disperse the crowd.
In total, more than 600 people have been arrested by police -- who were granted sweeping new powers before the summit began to detain anyone deemed a threat near the security zone in the heart of the downtown core.
Read More: G20 Protests Turn Violent in Toronto
"We're not sure we have the leaders, but we have a large proportion of those people and the people who decided they wanted to be influenced by these violent protesters and join with their cause," Toronto Police Sgt. Tim Burrows told the Associated Press. "A lot of them were home grown. There's a lot of Canadian talent in the group."
As the G20 summit was wrapping up Sunday evening, police warned journalists in downtown Toronto that officers in riot gear were preparing to use tear gas and rubber bullets on a group of protesters at the intersection of Queen Street and Spadina Avenue.
Several arrests were being made at the site, police said.
Early Sunday morning, one of the more unusual arrests of the weekend took place after four protesters were spotted emerging from a manhole in the Richmond and Bay Street area, near the city's financial district.
Witnesses spotted the suspects popping out of the sewer around 2:30 a.m. Afterward, city crews were called in to weld the manhole cover shut as officers inspected the system of sewers near the security zone.
"I don't know what they were doing down there," Jillian Van Acker, a spokeswoman for the summit's Integrated Security Unit, told the Canadian Press.
It's unclear how the protesters managed to gain access to the sewer system, as all of the manhole covers in the security zone were supposedly welded shut in the lead-up to the summit.
Elsewhere, about 50 people were rounded up near the University of Toronto after authorities found bricks and black clothing hidden in bushes.
Anarchists, mostly followers of the "Black Bloc" tactic of protesting, are largely being blamed for the chaos and violence that has gripped Toronto.
On Saturday, groups of rioters dressed in black broke off from a peaceful protest on Saturday and laid waste to banks, businesses, and police cruisers.
Windows were smashed, walls were defaced, and cars set on fire. The city responded by shutting down subway service to the downtown core and locking down many businesses and city services.
Some Torontonians wondered how police were unable to prevent the rampage, which left a trail of destruction rarely seen in the normally docile metropolis. Close to $1 billion is being spent on summit security, which includes an estimated 19,000 police officers from across Canada.
"How were 19,000 cops unable to control 100 anarchists?" one concerned citizen asked on Twitter.
With files from CBC News
