A protester confronts a police officer during a demonstration. (Ryan Remiorz/Canadian Press)

By CBC News

About 10,000 protesters were expected to march in Toronto on Saturday after rallies throughout the week ahead of the G20 summit.

Demonstrators said they want the main march from the grounds of the Ontario legislature to be peaceful, but there were worries a splinter group will break away and head to the security fence to confront police.

Tensions ran high during a protest Friday, when at least 3,000 people noisily marched through the downtown, snarling traffic. The march was organized by the Ontario Coalition Against Poverty and a group that campaigns for the rights of non-status immigrants.

Five people were arrested after some protesters refused to keep moving.

"They were throwing things at officers and carrying some contraband material that presented a pretty significant danger," Chief Bill Blair of the Toronto police told CBC News.

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