The woman in her 40s had warned her son that a U.S.-backed alliance would wipe out Islamic State and had encouraged him to leave the city with her.
She was detained after he informed the group of her comments, according to the British-based Observatory, which monitors the war through a network of sources on the ground.
Citing local sources, the Observatory 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.
This Mother had no chance. She challenged ISIS in it's own nest. She was crushed. Even if her son wanted to leave ISIS, the outcome might have been similar.
ISIS is evil. President Obama should not have enabled it.