ISIS leader Abu Bakr Al Baghdadi has anointed a successor, the militant group's propaganda arm said on Thursday.
If confirmed, the move could show that Al Baghdadi's health is deteriorating. The world's most-wanted terrorist leader was reportedly injured in fighting and last appeared in a video in late April.
Amaq news agency reported on Tuesday night that Al Baghdadi nominated as his successor Abdullah Qardash, an Iraqi of Turkmen origin from the Telafar region near the northern Iraqi city of Mosul, Turkish state news agency Anadolu reported.
Mosul was the last ISIS stronghold in Iraq before it was recaptured in a US-led campaign to defeat the group in that country and Syria.
Qardash, like Al Baghdadi, had been detained in Iraq by US forces that toppled Saddam Hussein in 2003.
He had served as a religious commissar for Al Qaeda before joining ISIS and welcoming Al Baghdadi in Mosul when the city fell to the group in 2014, Anadolu reported.
In his last public massage in April, Al Baghdadi said ISIS had launched a war of attrition ordained by God.
The announcement followed the defeat of the group by US-led Kurdish militia in eastern Syria and the killing of many of his lieutenants by US forces.
Al Baghdadi, who is in his late 40s, was sitting throughout the 18-minute video but otherwise did not show signs of ill health.
Unsubstantiated reports had described him as dead or wounded by US bombing, or living as a fugitive in Syria, Iraq and even Libya.