London: In a shocking low even by the standards of the Islamic State, a militant has publicly executed his own mother after accusing her of apostasy.

The activist group Raqqa is Being Slaughtered Silently (RIBSS) said 20-year-old jihadi Ali Saqr al-Qasem shot his mother Lena, 45, in the head with an assault rifle in front of a large crowd.

Lena al-Qasem is understood to have been accused of apostasy – a crime that usually means leaving one’s religion but in practise is used by ISIS as a justification for murdering anybody who doesn’t support or speaks out against the terror group.

The exact charge against Ms al-Qasem was “inciting her son to leave the Islamic State and escaping together to the outside of Raqqa”, according to the Syrian Observatory of Human Rights.

The UK-based conflict monitor said Ali Saqr al-Qasem had reported his mother to his ISIS superiors, who then sentenced her to death and ordered him be the one to kill her.