ISIS militants have executed a teenaged boy in Syria for being gay by throwing him off a roof.

The boy was executed in the eastern Syrian city of Deir ez-Zor according to local sources.

The 15-year-old was apparently arrested and charged by ISIS militants.

“The horrific execution took place in front of a large crowd,” a local activist in the city and an eyewitness told ARA News.

“The boy was accused of being engaged in a homosexual relation with the prominent ISIS officer Abu Zaid al-Jazrawi,” another activist told ARA.

According to the report, Abu Zaid was expelled to Iraq following the arrests.

“Abu Zaid was forced to leave Syria and join the fighting fronts in northwestern Iraq. The decision has been taken by the ISIS leadership,” the second activist said.

Pro-ISIS sources said the man was tried in Sharia court, and ISIS militants had wanted him to be executed, but that he was allowed to join forces in Iraq instead.

The group has executed hundreds of men for homosexuality as it expands beyond its strongholds.

The United Nations Security Council recently discussed the group’s tactics in persecuting LGBT people, as well as spreading terror and committing other atrocities.