REPORT: Russia's military says it may have killed IS leader; West, Iraq skeptical

The secretive Islamic State leader has frequently been reported killed or wounded since he declared a caliphate to rule over all Muslims from a mosque in Mosul in 2014, after leading his fighters on a sweep through northern Iraq.

If the report does prove true, it would be one of the biggest blows yet to Islamic State, which is trying to defend its shrinking territory against an array of forces backed by regional and global powers in both Syria and Iraq.

But in the absence of independent confirmation, two US officials said US agencies were skeptical of the report. Several Iraqi security officials said Iraq was doubtful as well.

"His death has been reported so often that you have to be cautious till a formal Daesh statement comes," a European security official said, using an Arabic acronym for the group.

US Navy Captain Jeff Davis, a Pentagon spokesman, said: "We have no information to corroborate those reports."

The Russian Defense Ministry said on its Facebook page that it was checking information that Baghdadi was killed in the strike on the outskirts of Raqqa in Syria, launched after Russia received intelligence about a meeting of Islamic State leaders.

"On May 28, after drones were used to confirm the information on the place and time of the meeting of IS leaders, between 00:35 and 00:45, Russian air forces launched a strike on the command point where the leaders were located," the statement said.

"According to the information which is now being checked via various channels, also present at the meeting was Islamic State leader Abu Bakr al-Baghdadi, who was eliminated as a result of the strike," the ministry said.

However, a colonel with the Iraqi national security service told Reuters Baghdadi was not believed to have been in Raqqa at the time of the strike in late May. One of Baghdadi's aides may have been killed rather than Baghdadi himself, the colonel said.

He said that Baghdadi was believed to be operating cautiously in the border area between Iraq and Syria with just a handful of close aides, and avoiding using telecommunications equipment to evade surveillance.

Another Iraqi intelligence official said the Russians had not shared any information with Iraqi authorities to indicate Baghdadi was killed. Iraq was checking the report and would announce his death if it received "solid confirmation".