A top Kurdish counter-terrorism official said on Monday he was 99 per cent sure that ISIL leader Abu Bakr Al Baghdadi was alive and located south of the Syrian city of Raqqa, despite reports that he had been killed.
"Baghdadi is definitely alive. He is not dead. We have information that he is alive. We believe 99 per cent he is alive," said Lahur Talabany.
"Don't forget his roots go back to Al Qaeda days in Iraq. He was hiding from security services. He knows what he is doing."
The secretive ISIL leader has frequently been reported killed or wounded since he declared a caliphate from the Grand Al Nuri mosque in the Iraqi city of Mosul in 2014.
Also on Monday, Moscow said it was struggling to confirm if Al Baghdadi was dead or alive, a month after reporting his possible demise.
In June, the Russian army said it was trying to verify information that its jets had killed Al Baghdadi during a bombing raid near the ISIL stronghold of Raqqa in Syria.
But over a month after the announcement, Kremlin spokesman Dmitry Peskov said Russia still had "no more precise information" on Al Baghdadi's fate.
"The information coming in is contradictory and is being checked by the relevant agencies," he said.
Al Baghdadi may now be a man on the run, if not dead, but he is still a cunning foe, said Mr Talabany, who, as part of the US-led coalition against ISIL, has been at the forefront of efforts to track Al Baghdadi down.
"He is not an easy figure. He has years of experience in hiding and getting away from the security services," Mr Talabany added.
Iraqi security forces have ended three years of ISIL rule in Mosul, and the group is under growing pressure in Raqqa — the extremist group's former strongholds.
Mr Talabany said ISIL was now shifting tactics despite low morale and that it would take three or four years to eliminate the group as it takes to the mountains and deserts to stage hit and run attacks and unleash suicide bombers.
"They are getting ready for a different fight I think. We have a lot tougher days ahead of us than people think. Al Qaeda on steroids," he added.
Mr Talabany's remarks came as US-backed Syrian fighters clashed with ISIL militants in the heart of Raqqa on Monday.
The Kurdish-led Syrian Democratic Forces alliance, aided by the US-led coalition, launched its offensive to capture the city on June 6, and has since taken several areas.
The Syrian Observatory for Human Rights, a Britain-based monitoring group, said Monday's fighting was concentrated in the southwestern neighbourhood of Yarmouk as well as a central area close to the Old City.
The SDF said 11 ISIL fighters had been killed in the clashes since Sunday, while ISIL's Amaq news agency said 14 SDF fighters had been killed in the fighting in Raqqa on Sunday alone.
* Additional reporting by Associated Press and Agence France-Presse