For the hundreds of protesters who gathered at Dorchester Square Sunday, Canada’s military involvement in the fight against ISIS is nothing short of illegal.

One of the event’s organizers says ISIS combatants in the Middle East were largely ignored by the West until Western interests were threatened.

“The reason is that ISIS has now managed to control a good part of northern Iraq and is threatening to overthrow the government in Iraq and therefore taking over a country where there's a whole lot of oil,” said Raymond Legault, spokesman for the anti-war group “Collectif echec a la guerre.”

The House of Commons voted this month to commit fighter jets and hundreds of support personnel in the U.S.-led coalition fighting Islamic extremists in Iraq.

But the protestors say Canada should withdraw - that the responsibility of fighting ISIS should rest primarily with people in the region.

The protest began at Dorchester Square where just 24 hours earlier people had gathered for a memorial to the two soldiers killed in the last week.

Corporal Nathan Cirillo was shot to death in Ottawa Wednesday while standing guard at the national war monument.

And warrant officer Patrice Vincent died last Monday after he was run down in St. Jean sur Richelieu.

In that case the attacker had been recently drawn to Islamic extremism.

Quebec solidare MNA Amir Khadir says radicals should be fought - but military strikes are not the way.

“After what has happened this week of course we need a strong response. But strong can be in intelligence, in measures and policies that won't perpetuate what we have done in the last ten years,” he said.

Earlier in the day members of Montreal’s Muslim community launched a campaign to combat extremism in the west.

“It was being done in the name of religion which promotes peace and which has absolutely nothing to do with such acts,” said Luqman Ahmed, a Quebec City imam.

Ahmed says groups like ISIS twist the teachings of Islam turning some into radicals.

“They’re being used for a purpose which Islam does not permit and they're being used for political purposes and Islam has no place for such acts,” he said.

His comments echo the statements made on a Facebook page called “Pas en mon nom,” created by a Muslim teen living in Montreal who wants fellow young Muslims to denounce the actions of radicals.