The director of the war monitor was quoted as saying by news agencies that 'top tier commanders from IS who are present in Deir Ezzor province have confirmed the death of Abu Bakr al- Baghdadi, emir of the Islamic State group, to the observatory'.
Though, IS news agency Amaq has not confirmed it yet.
The Pentagon, Kurdish and Iraqi sources were all quick to say they could not corroborate the SOHR report.
Rumours of Baghdadi's death have been frequently reported in the past.
Last month, Russia claimed to have killed Baghdadi in an air strike in Raqqa.
Baghdadi has not been seen in public since proclaiming himself caliph in the Iraqi city of Mosul three years ago.
Baghdadi had declared the Islamic State's caliphate from the pulpit of Al-Nuri Mosque in Mosul in July 2014.
Iraq on Thursday announced the end of Islamic State in the city of Mosul that has been under seizure of the extremist groups for three years.
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