MOSCOW - The Russian army on Friday said it hit Islamic State leaders in an airstrike in Syria last month and was seeking to verify whether IS chief Abu Bakr al-Baghdadi had been killed.

In a statement, the army said Sukhoi warplanes carried out a 10-minute nighttime strike early on May 28 at a location near Raqqa, where IS leaders had gathered to plan a pullout by militants from the group's stronghold.

"Senior commanders of the military groups of the so-called IS military council, 30 mid-ranking field commanders and up to 300 militants who provided security for them were eliminated," it said.

"According to information which is being checked through various channels, Baghdadi, leader of the IS group, was also present at the meeting and was eliminated by the strike," it said.

If confirmed, it would mark a major military success for Russia, which in September 2015 launched a bombing campaign in Syria against IS extremists.

The strike on May 27 followed confirmation of the meeting by a drone. Those killed included the emir of Raqqa and the IS security chief, the statement said.

The US has been informed about the attack, the statement added.

Elusive IS supremo Baghdadi has not been seen in public since proclaiming himself "caliph" in the Iraqi city of Mosul three years ago.

His group has earned global notoriety for imposing a hardline form of Islam that has included stonings, beheadings and amputations.

The Iraq-born world's most-wanted man has been rumored wounded or killed a number of times in the past.

He has been nicknamed "The Ghost" as he has been reportedly spotted around the Syrian-Iraqi border but his whereabouts have never been confirmed.

In March, US Secretary of State Rex Tillerson declared that Baghdadi's death is imminent since "nearly all" of his deputies are dead and "it is only a matter of time" before the IS chief himself meets the same fate.

On Friday, the US-led coalition also battling the IS group said it could not confirm the death of Baghdadi.

Afp - Ap