OTTAWA – Canadian military aircraft involved in the fight against Islamic State militants have not flown over Syria for the past few weeks, though a senior officer denied any links Friday to Russian threats.Tensions erupted last month after Moscow warned that it would track allied aircraft operating west of the Euphrates river in Syria as potential targets in retaliation for the U.S. shooting down a Syrian government jet.National Defence refused at the time to say whether there was any concern for the Canadian military surveillance or refuelling planes flying over Syria and Iraq as part of the U.S.-led anti-ISIL coalition.In an interview with The Canadian Press on Friday, Brig.-Gen. Daniel MacIsaac said the planes have been operating exclusively in Iraq for several weeks — though he insisted it was not because of Russia.“We are busy and contributing very well in Iraq right now,” said MacIsaac, who took over as commander of Joint Task Force-Iraq in February. “Right now, our (aircraft) have ample work to do in Iraq.”Canadian aircraft have not been targeted by Russian or Syrian air defences, he added.Defence officials would not say when Canadian aircraft last flew over Syria, citing operational security. But they did reveal that earlier this year the planes flew dozens of missions over the war-ravaged country, where ISIL is under pressure from U.S. and local forces.The war against ISIL has entered a new phase since Iraqi officials announced earlier this month government forces had finally liberated the city of Mosul after nine bloody months of fighting.The victory has been bittersweet — it represented a major blow to the extremist group but tens of thousands of civilians are believed dead.While some might believe the worst is over, ISIL, or Daesh, continues to hold large swaths of territory, MacIsaac noted.“Let me say right off the bat: The job in Iraq is not done. The job in Iraq is not done,” he said.Canadian forces have been specifically focused on mapping one part of Iraq and identifying potential targets for coalition operations, MacIsaac said, though he declined to say where.“There are still large concentrations of Daesh forces,” he said, estimating the number of fighters in both Iraq and Syria at between 10,000 and 20,000. “We are very busy.”MacIsaac’s command includes surveillance and refuelling aircraft as well as a transport plane and an intelligence unit in Kuwait, plus a helicopter detachment and a military hospital in northern Iraq.Canada also has about 200 special forces troops in northern Iraq, some of whom have been operating inside Mosul and along the border with Syria, but they fall under a different commander.The Liberal government recently extended Canada’s mission against ISIL until March 2019, while giving the military more flexibility to decide on its own what it needs to accomplish its objectives.Exactly what form the mission will take over the next two years remains almost as uncertain as what will happen in Iraq in coming months.There are fears that ISIL is poised to go underground and resort to traditional terror tactics such as suicide bombings, which will require different training from what Canada and its allies have already provided.MacIsaac said he was unable to comment on reports that two Canadian women had been found in a tunnel under Mosul and detained by Iraqi forces for alleged links to ISIL.Canadian diplomats have been working to verify the report, though a senior government official cast doubt Thursday on whether it was true.— Follow @leeberthiaume on Twitter.