Canadian special forces returned ISIS fire in Iraq sometime in the last week when they went to the front lines following a planning session with senior Iraqi leaders, their commanding officer told reporters in Ottawa on Monday.

Brig.-Gen. Michael Rouleau, commander of the Canadian special operations forces command, said the forces came under "immediate and effective mortar fire" and responded with sniper fire, "neutralizing the mortar and the machine-gun position."

The troops had been in a planning session several kilometres behind the front lines, but approached to visualize what they had discussed.

Rouleau said he couldn't provide much tactical detail to avoid giving ISIS an advantage in future.

He said the response was consistent with the inherent right of self-defence and suggested it was an incident typical of military missions, one that wouldn't have been unusual even in past Canadian peacekeeping missions.

The House voted in October in support of an air combat mission, but the government has said Canadian Forces won't be involved in ground combat in Iraq.

A spokesman for Prime Minister Stephen Harper described a combat role as one in which troops advance and seek to engage the enemy "physically, aggressively, and directly."

'Advice and assistance' only

"That is not the case with this mission," Jason MacDonald wrote in an emailed statement.

"This mission is one in which they are providing advice and assistance to Iraqi forces only.... That said, we have always been clear that while this is a low-risk mission, it is not without risk and our forces on the ground will protect themselves if fired on in the course of carrying out their mission."

Last September, before MPs voted to support an air combat mission, NDP Leader Tom Mulcair asked Harper whether Canadian soldiers would be going into combat zones.

"Canadian soldiers are not accompanying the Iraqi forces into combat," Harper responded.

Mulcair then asked whether Canadian Forces had assisted in targeting ISIS. Harper reiterated that the purpose was to "assist and to advise the Iraqi forces."

"While there is some risk, there is not a direct combat role," Harper said Sept. 30.

Elliot Tepper, a senior research fellow with Carleton University's Centre for Security and Defence Studies​, said Canada's mission hasn't changed because the special forces exchanged fire with somebody.

"But it does remind everyone that we have Canadians in harm's way in a war zone," he said.​

Lt.-Gen. Jonathan Vance, commander of the Canadian joint operations command, said coalition forces have stopped the advance of the Islamic State in Iraq and Syria, also known as ISIS or ISIL.

ISIS has been forced into a defensive posture, he said.

'Degrading' ISIS

"Now we are degrading them," Vance said of the three-month-old mission.

"We have disrupted their freedom of manoeuvre, their command and control capabilities and limited their ability to carry out large-scale operations."

Despite that, Vance said, "the complete degradation and defeat of ISIL will likely take years."

Tepper agreed with that assessment.

"We've got this almost demonic force which seemed unstoppable, which has now been stopped. Degrading, however, will indeed be a long-term and problematical, very problematical, task to achieve. We aren't sure it is achievable at this point.

The government has said it will consider extending the six-month mission and would consider including Syria in the operation.

"The Armed Forces are prepared and preparing to extend if we're told. And we are prepared to return home and redeploy if we're told to do that," Vance said.

U.S. reports 15 airstrikes yesterday

The government had also approved a plan in September to send 69 special forces soldiers to northern Iraq to assist local forces in the fight against ISIS, although Harper confirmed Oct. 1 that there were only 26 special forces troops on the ground.

Those special forces are drawn from four areas:

Joint Task Force 2.

Canadian Special Operations Regiment.

427 Special Operations Aviation Squadron.

Canadian Joint Incident Response Unit.

The U.S. Central Command issued its own mission update Monday, reporting 15 airstrikes against ISIS forces in Syria and another 11 against positions in Iraq in a 24-hour period between 8 a.m. Sunday and 8 a.m. Monday local time. The airstrikes were conducted by U.S. and coalition forces using fighter jets, bombers and remotely piloted aircraft, the release said.

The release did not say which members of the coalition, which includes Canada, took part in the operations.

The targets struck in northern Syria included ISIS units near Kobani, Aleppo and Al Hasakah. The Al Hasakah airstrikes hit an artillery system, the release said.

In Iraq, the operations targeted ISIS units and buildings in seven areas, including near Mosul and Baghdad. All aircraft returned safely from the sorties, the release said.