Montreal police have arrested two demonstrators and fined two more, as a group of protesters clashed with police at a demonstration against Quebec's proposed Northern Plan mining project in Montreal on a frigid Monday morning.

Two will be charged with assault, according to police.

“Age 28 and the other one aged 22 were arrested for armed assault on police officers. The 28-year-old was also charged with the P6 bylaw infraction for wearing a mask,” said Montreal police spokesperson Laurent Gingras.

Police say the two men were released with a promise to appear in court to face the charges.

Two others face fines for municipal bylaw violations.

“We intercepted two persons for municipal by-law infractions. These two individuals refused to walk,they refused to leave they were at when police officers approached them. They were released with a bylaw infraction ticket,” said Gingras.

The protesters were participating at an early morning demonstration near the Palais de Congres where Natural Resources Minister Pierre Arcand was set to speak to the Montreal Chamber of Commerce in a forum on natural resource development.

The protesters also hurled paint at the windows of the conference centre and affixed stickers to windows expressing their opposition to mining in Quebec's far north.

The protest was organized by the ASSE student group.

“We don't have the right to protest if we don't give our itinerary to the police, which is totally ridiculous,” said protester Marc Laramee.

As protesters tried to block the streets, they were confronted by riot police officers trying to break up the illegal demonstration, and the tension quickly escalated.

“It happened very suddenly. The cops just came out of nowhere and they just beat the crap out of people who were just holding a banner. It's totally ridiculous,” said Laramee. 

“Obviously you have the right to protest peacefully, but from the time that you're assaulting police officers with sticks, I don't think we're talking about a peaceful protest at that point,” countered Gingras.

After the clash, the angry standoff between protesters and police continued. When protesters changed directions and started running, police officers followed.

By noon, most of the protesters had dispersed.