Police used tear gas and pepper spray against protesters who were hurling rocks and branches during confrontations outside the leaders summit in Quebec on Monday.
Police arrested at least one protester in the small resort town of Montebello, near Ottawa, where Canadian Prime Minister Stephen Harper is meeting with U.S. President George W. Bush and Mexican President Felipe Calderon to discuss issues including border security and free trade.
The leaders began their talks Monday inside the Fairmont Le Château Montebello hotel, whichis being protected by afour-metre security fence and police in riot gear who are patrolling the area on foot, in cars, on motorcycles and in helicopters.
At least 500 protesters took part in a march outside the hotel, carrying signs with slogans such as "No to Americanada." Others held a peaceful family-friendly rally away from police lines.
Many protesters arrived to the site by the busload from cities including Montreal, Kingston and Ottawa.
Harper dismissed the demonstration after he was told hundreds of protesters were involved.
"I've heard it's nothing. A couple hundred? It's sad," he said.
'We're going to protest where we want to protest'
Some of the demonstrators went to designated protest areas — one in an empty field and the other a picnic area — whileothers chose to walk down Route 148 toward the hotel.
Some protesters decried the use of designated protest areas, calling them "protest pens."
"They're like cages and they want to keep people in an area where they can manage them," said Trevor Haché, who was part of a caravan of cyclists who rode from Ottawa to join the protest. "We're going to protest where we want to protest. It's our democratic right."
The two-day summit is set to focus on thebroad-ranging Security and Prosperity Partnershippact signed in 2005by the Canada, Mexico and the United States.
The SPP, meant to complementtreaties such as the North American Free Trade Agreement, was created to boost co-operation on security, trade and public-health issues among the three countries.
But protesters say the SPP is anti-democratic because it didn't require a vote in Parliament or a change in the law.
"If this is such a wonderful deal and it is about protecting North Americans from shoddy products or whatever they're now saying… then be proud of it, stand up, tell us what's in it… and send it to our Parliament for oversight," Maude Barlow, head of the Council of Canadians, said in an interview from Ottawa Monday morning.
Barlow said the SPP forces Mexico and Canada to adoptBush's notions of security, "kind of putting a zip-lock of a security perimeter around North America."
Concerned about Canada losing control
Manyprotesters said they are concerned about Canada losing control of its energy, water resources and border as initiatives such as the SPP treaty increase and expand.
While Harper has offered assurances that won't happen, many of the protesters said Sunday they don't believe him.
"I think ultimately, his allegiance is to the corporate kind of world," demonstrator Andy Elliott told CBC News. "He doesn't seem too concerned for the average person."
The demonstrators are also decrying the secrecy surrounding the meeting and that the only people with access to the three leaders at the summit are 30 chief executives of some of the biggest corporations in the world.
But Thomas D'Aquino, president of the Canadian Council of Chief Executives, said getting access to political leaders is not the only way to be heard.
"I do not say to myself, 'If I don't get an hour with the prime minister in the next six months, I'm going to go out and protest and reject the system outright,' " he said.
"I don't do that because civilized human beings — those who believe in democracy — don't do that."
Canadian government officials said the three leaders will be able to see and hear the protesters through a video link inside if they choose to watch.