ISIS leader Abu Bakr al-Baghdadi has been poisoned in Iraq by a suspected assassin, according to a report by the Iranian news agency FARS.
Fox News World, quoting from the report, said Baghdadi is in critical condition as a result of being administered with the toxin near Mosul, Islamic State's biggest city in Iraq.
Three other senior ISIS officials were also recovering from similar injuries, the reports said.
Baghdadi was personally responsible for the rape and torture of U.S. aid worker Kayla Mueller, captured at 26, who died in a Jordanian air strike against ISIS in February 2015.
Baghdadi, a former U.S. prisoner in Iraq, went on to head ISIS in Iraq in 2010. Baghdadi has only appeared in public once since he declared himself emir (leader) of the Islamic State in June 2014, but he was considered among the most feared terrorist leaders in the world.
There have been several reports in the past that Baghdadi, whose real name is Ibrahim al-Samarrai, was killed or wounded after proclaiming himself caliph of all Muslims two years ago.
The ultra-hardline Sunni group is under increased pressure in both Iraq and Syria, and the territory under its control has shrunk significantly since 2014, limiting the potential for its leaders to move around or seek shelter.
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