Eight senior figures from Islamic State have been killed in an air strike in western Iraq, but the group's leader Abu Bakr al-Baghdadi did not appear to be among them, local residents and hospital sources say.

Iraq said on Sunday its air force had hit a meeting of IS members and had also struck a convoy that was carrying Baghdadi to attend it.

It said Baghdadi had been driven away from the convoy in an unknown condition.

"Iraqi air forces have bombed the convoy of the terrorist Abu Bakr al-Baghdadi while he was heading to Karabla to attend a meeting with Daesh commanders," the Iraqi military said in a statement, using the Arabic word for the group.

"The location of the meeting was also bombed and many of the group's leaders were killed and wounded. The fate of murderer al-Baghdadi is unknown and he was carried away by a vehicle. His health condition is still unclear," the military said.

Local residents in Karabla, near the Syrian border, said eight IS leaders had been killed in an air strike, but that Baghdadi did not appear to be one of them.

A Twitter account that publishes statements from IS said "rumours" that an air strike had targeted Baghdadi were false.

The United States military declined to comment on the Iraqi military's report.

An IS fighter reached by telephone said he could not confirm whether Baghdadi had been in a convoy that was struck, but said the group would fight on whatever his fate.

"Even if he was martyred then it will not affect Islamic State," the fighter said.

"We will lose a leader but there are a thousand Baghdadis. Every minute a leader is born in the Islamic State."

Mystery surrounds IS chief

Iraqi interior ministry spokesman Saad Maan told AFP that "the strike was yesterday [Saturday] at noon".

He said the operation was conducted in coordination with Iraq's interior ministry intelligence services and the joint operation command centre, which includes military advisers from the US-led coalition.

Iraqi security sources have reported previously that Baghdadi had been injured or killed in strikes in the past but the claims were either never verified or later denied.

The health and whereabouts of Baghdadi, who has a $US10 million ($13.6 million) bounty on his head, are the subject of constant speculation.

He was reported wounded multiple times over the past year and his apparent survival has only added to the mystery surrounding the IS chief.

In November last year, US-led strikes hit "a gathering of leaders" of IS near Mosul, but the US Central Command said it could not confirm if Baghdadi was among the group. A month later, air strikes killed his deputy, Haji Mutazz, the Pentagon said.

According to an official Iraqi government document, Baghdadi was born in Samarra in 1971 and has four children with his first wife — two boys and two girls born between 2000 and 2008.

But Baghdadi has only appeared once in public since taking the helm of the movement, in June 2014 at a mosque in the northern Iraqi city of Mosul.

In his sermon, he asked all Muslims to obey him and join the caliphate.

The Iraqi military statement was released by the "war media cell", a structure which provides updates on the war against IS and speaks for the interior and defence ministries as well as the paramilitary Popular Mobilisation forces.

IS has seized swathes of Syria and Iraq and in June declared a caliphate over territory it controls.

Baghdadi has said he had accepted oaths of allegiance from supporters in Libya, Egypt, Yemen, Saudi Arabia and Algeria.

AFP/Reuters