The RCMP and Quebec police force have denied allegations their officers posed as protesters to try to provoke peaceful demonstrators at the recent Montebello summit.

"I confirm (to) you that there is no agents provocateurs in the Surete du Quebec... It doesn't exist in the Surete du Quebec," spokesperson Const. Melanie Larouche told The Canadian Press.

RCMP Cpl. Luc Bessette said the Mounties do "not use tactics that would encourage confrontation or incite violence."

A video posted on YouTube from Monday's protests in Montebello, Que. shows Communications, Energy and Paperworkers Union of Canada (CEP) President Dave Coles in a confrontation with three masked men who appear to be protesters.

"I accused them of being police, and every time I yelled at them that they were police, you could tell by their facial expressions that they were really troubled," Coles told CTV Newsnet Wednesday.

He added that the men "weren't young kids off the streets, they were there to deliberately cause trouble, to give the police a chance to try and get rid of these young kids that were exercising their right to protest peacefully."

In the video, Coles and other protesters tell the men to take off their masks. One of the three men is holding a rock and Coles tells him to move because their line is meant for peaceful protesters.

"These three guys are cops, everybody!" Coles can be heard shouting to the crowd as he tries to pull down their bandanas.

The three men then push their way into the police line and appear to be arrested, then taken away.

In the video, Coles claims the men were sent as provocateurs to give the police an excuse to move in on demonstrators.

"I looked him in his eye and said 'You're a cop aren't you?' and his eyes just glazed right up," Coles tells a crowd in the video.

Photographs taken by another protester show the three men lying on the ground with the soles of their boots adorned by yellow octagons. A police officer kneeling beside the men appears to have the same imprint on his boot.

The imprint appears to be the Vibram boots logo. Earlier reports had suggested it was a yellow triangle signifying Canadian Standards Association-approved footwear.

Police have confirmed that only four protesters, not the men in the video, were arrested during the summit.

"But we see very clearly in that video three (other) men being arrested . . . How do (police) account for these three people being taken in, being arrested? Where did they go?" veteran protester Jaggi Singh asked CP Tuesday.

"I have no hesitation in saying they were police agents... and they were caught red-handed."

Despite denials from both the RCMP and Quebec police, Liberal justice critic Marlene Jennings said the evidence is "quite incriminating" and told them to "clear this up."

Meanwhile, New Democrat MP Libby Davies said the video raises "hugely serious questions" about how police act at international meetings.

"It seems like they create this environment, a show of force, that sets it up for a confrontation,'' said Libby who protested at the summit.

"I think we need to know who authorized this, how high up does this go?"

Prime Minister Stephen Harper, U.S. President George Bush and Mexican President Felipe Calderon, wrapped up the summit Tuesday.

Many activists were protesting what they perceived a lack of transparency surrounding the North American Security and Prosperity Partnership (SPP) process.

The two-year-old framework is being used to pursue greater trade and security integration between the three countries.

While a group of top business executives got the chance to make a presentation to the three leaders on Tuesday, no such invitation was extended to environmental or social activists.

Critics claim the SPP is a 'super-NAFTA' that will result in stolen jobs and an erosion of freedoms.