The heads of state of 34 nations from North and South America and the Caribbean continued talks on Saturday, the second day of the summit, within a 2.3-mile (3.7-kilometer)-long chain-link and concrete fence surrounding the venues.
Outside and on the perimeter, it was a battle zone. Demonstrators pulled down several sections of fence with their bare hands or with ropes, or severed its links with bolt cutters. But each time, police drove them away with volleys of tear gas, with truck-mounted water cannons, rubber bullets and stun grenades.
Unrest continued through the night along the riverfront, far from the summit venues, with protesters smashing windows and setting fires on some streets.
At the Holiday Inn Select hotel, manager Lyne Bergeron said a few windows were broken, and one had a large metal bar through it. Nothing was stolen, and police reported Sunday they arrested 253 people overnight.
Streets were quiet on a rainy Sunday orning, but security remained tight in case of more protests.
Some observers and participants were upset at the level of violence.
"I know nothing about free trade, but I know the cops are pushing too much," said Gaetan Gingras, who stood outside his home and offered cool water from a hose to protesters whose eyes were streaming from tear gas.
Many oppose a free-trade zone because they feel it will enrich corporations at the expense of the poor, risk jobs at home and because it is being negotiated without their consent. But some of the tens of thousands of protesters - most of whom demonstrated peacefully - thought some demonstrators who were trying to harm police or vandalizing property were going too far.
Protesters hurled rocks, bottles and firebombs at police and even used hockey sticks to slapshot tear gas canisters back at the anti-riot officers.
"Go and confront the police. Don't destroy property. It gives us all a bad image," admonished Sel Burrows, a 57-year-old protester from Thompson, Canada.
Burrows turned to a journalist. "They're just crazies," he said. "They don' represent the rest of us."
Some of the police officers, weary after pulling long shifts, even sympathized with the demonstrators' viewpoint.
"I agree 100 percent with the protesters, but not with the hooligans who are attacking us," one riot policeman who insisted on anonymity said in an interview. "This free-trade proposal bears watching. I have children, and I want them to have a chance to do well and be able to make a living."
By Sunday morning, 403 people were reported arrested over the two days and 57 protesters and 46 police officers injured, none seriously. The summit ends on Sunday.
By Andrew Selsky
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