This file image made from videoin 2014 purports to show the leader of the Islamic State group, Abu Bakr al-Baghdadi, delivering a sermon at a mosque in Iraq. File picture: Militant video/AP

Ankara - Islamic State's leader Abu Bakr al-Baghdadi is definitely dead, Iran's state news agency quoted a representative of Iranian Supreme Leader Ayatollah Ali Khamenei as saying on Thursday.

"Terrorist Baghdadi is definitely dead," cleric Ali Shirazi, who is representative to the Quds force, told IRNA without elaborating.

The secretive Islamic State leader has frequently been reported killed or wounded since he declared a caliphate to rule over all Muslims from a mosque in Mosul in 2014, after his fighters seized large areas of northern Iraq.