On the streets of Toronto, where the world leaders are meeting, thousands of people were out to demonstrate against the event. However, what started off as a peaceful rally, transformed into ugly scenes as anarchists, dressed in black, broke away from the main group.
At least two police cars were set on fire, one in the financial district of the city.
Shop fronts were destroyed, as people wearing masks continued to cause havoc, moving to just blocks away from the three meter fence around the summit site.
Police in riot gear made a number of arrests, and some streets leading to the downtown part of the city were sealed off.
The city’s mayor condemned the violence, saying a relatively small group are intent on damaging property and breaking the law.
Canadian authorities have been taking security very seriously during the summits, spending almost eight hundred million euros.