The Isis leader, Abu Bakr al-Baghdadi, was probably not present in a convoy of vehicles targetted in air strikes by the Iraqi military, officials have said.
On Sunday, the Iraqi air force said it had launched successful attacks on a meeting of Isis commanders near the Syrian border, as well as a convoy thought to be carrying the leader to the event.
In a statement released on Monday, however, a senior Iraqi security official said that intelligence - provided by the US-led coalition against Isis - may have been inaccurate.
"After assessing all information we received from our sources, it's more likely that the convoy we struck was not carrying Abu Bakr al-Baghdadi," he said.
"We are still carrying out extensive efforts to clarify the situation."
Hospital officials have confirmed that at least eight Isis commanders were killed in the strikes in Iraq's Anbar province, but said al-Baghdadi's body was not among them.
The Iraq military's initial statement on the strikes had described al-Baghdadi's fate as "unknown". It was initially thought that a car may have carried the leader away from the scene.
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