The Syrian Observatory for Human Rights reported on Friday that an Islamic State militant executed his mother in public in the Syrian city of Raqqa.
The woman believed to be in his 40’s is believed to have been killed by her son because she had encouraged him to leave the group.
She told her son to leave the town with her because she feared a U.S.-backed alliance would wipe out Islamic State soon.
The son immediately informed the group of her comments which led to her being arrested.
The Islamic State group, which controls wide areas of Syria and Iraq, usually executes people they thought were working with its enemies and has already executed hundreds of people it has accused of breaching its ultra-conservative interpretation of Islam.
The British-based Observatory, which monitors the war through a network of sources on the ground, cited local sources, which said the 20-year-old man executed his mother on Wednesday near the post office building where she worked in front of hundreds of people in Raqqa, a main base of operations for the group in Syria.
The Observatory had reported on Dec. 29 that Islamic State had executed more than 2,000 Syrian civilians in the 18 months since it declared its "caliphate" over the territory it controls in Syria and Iraq. They included people killed on the grounds of homosexuality, practicing magic and apostasy.
The latest report was not possible to be independently verified.