Russia is investigating whether one of its air strikes killed Islamic State leader Abu Bakr al-Baghdadi.

The Russian Defense Ministry said on Friday it was checking on information indicating that Baghdadi was killed in a Russia-led airstrike in Syria.

Russian Su-34 aircraft and an Su-35 multirole fighter carried out airstrikes near the Islamic State of Iraq and the Levant (Isil) stronghold of Raqqa in northern Syria on May 28, the ministry said.

The strikes targeted a meeting of high-ranking Isil chiefs where Baghdadi was reportedly present.

It said the air raid on the southern outskirts of the city killed about 30 mid-level militant leaders and about 300 other fighters.