OTTAWA -- There have been two more firefights between Canadian special forces troops and militants in the Middle East -- clashes sure to fan the flames of a raging political debate about Canada's evolving combat mission in Iraq.

The elite troops were helping Kurdish commanders plan for an upcoming operation and twice came under direct fire while visiting the largely static front lines near Irbil, the military disclosed Monday.

In both cases the Canadian troops returned fire and "neutralized" the threats, navy Capt. Paul Forget told a weekly technical briefing at National Defence headquarters.

"They were acting in self defence," Forget said.

As the House of Commons resumed Monday, New Democrats launched a political volley of their own, calling on Speaker Andrew Scheer to convene an emergency debate on the "growing expansion of this mission."

During question period, both Liberal Leader Justin Trudeau and NDP Leader Tom Mulcair accused the government of having misled the public when it promised there would be no ground combat for troops.

"How many gun battles, how many airstrikes, how many targets painted by our troops on the ground before the prime minister and this minister admit that our troops are in a combat mission?" Mulcair asked.

"Stop playing with words. Our troops deserve better."

The latest gun battles follow on the heels of an incident described last week by the commander of special forces, Brig.-Gen. Michael Rouleau, whose news conference helped to jump-start the dormant political debate in Ottawa.

Operations involving the highly trained soldiers, who were deployed to advise and assist Iraqi forces last September, are usually covered by a blanket of secrecy.

Rouleau acknowledged that his troops had on 13 occasions helped direct U.S-led coalition airstrikes to targets near the front line in what opposition parties are calling an escalation of Canada's combat involvement in Iraq.

Canadians have not directed any further bombing missions since the last update, the military said.

Forget, like Rouleau the week before him, insisted Monday that the nature of the operation was "evolving," and that special forces trainers were at the front to supervise Iraqis as they put their instruction to the test.

Defence Minister Rob Nicholson took a similar tack in question period Monday, saying Canadian troops can't do the job without "accompanying" Iraqi forces. That contradicts Prime Minister Stephen Harper, who told the Commons last fall that the special forces role was to "advise and to assist. It is not to accompany."

During the Kandahar combat mission, Canadian troops would accompany Afghan soldiers, whom they were mentoring, into combat. It was a dangerous exercise that sometimes led to casualties.

Both the Conservative government and the military ruled out a similar scheme when it deployed the special forces into Iraq.

Despite the firefights, the risk assessment for trainers remains low, Forget said. But he was unable to say whether they are spending more time at the front as Iraqi forces prepare for an offensive to retake territory from the Islamic State of Iraq and the Levant.

Airstrikes, meant to soften up the ground for that offensive, have continued and they included 12 bombing missions by Canadian CF-18s during the last week, Forget said.

Most of the bombs were dropped northwest of Mosul, the country's second largest city. The Iraqis have been conducting a localized offensive in the region near Tal Afar in an attempt to cut extremist supply lines coming in from Syria.

The escalation in the political debate in Canada came on the same day as an audio recording purportedly from ISIL leaders emerged, encouraging Muslims living in Western countries to carry out more attacks -- and calling out Canada by name.

"You all saw what one Muslim did in Canada and its infidel parliament," says the voice on the recording, said to be that of Abu Mohammed al-Adnani, in reference to the Oct. 22 attacks in Ottawa.

Al-Adnani also praised recent attacks in Australia, Belgium and France, where gunmen killed 12 people in an assault on the Paris office of Charlie Hebdo magazine.