Warning: graphic images below
A mass grave has been discovered in eastern Syria that is holding the bodies of more than 230 people thought to be victims of the Islamic State (IS), activists have reported.
The dead are allegedly members of the al-Shaitaat tribe, which fought the jihadist group during the summer, according to UK-based monitoring group the Syrian Observatory for Human Rights.
The discovery would tally with a United Nations report released last month that said investigators had discovered evidence of a massacre in the same area of Deir Ezzor province in August 2014.
The report claimed that the slaughter was perpetrated in a struggle for control of oil resources near the town of Mohassan, and that the victims were fighting-age males.
It quotes one survivor who described seeing "many heads hanging on walls while I and my family escaped."
Individuals living in the area also reported seeing freshly-dug mass graves.
IS leader Abu Bakr al-Baghdadi reportedly issued a statement on November 6, which granted members of the tribe permission to return to their homes after they "declared their repentance." Al-Baghdadi also laid out a further list of prohibitions that included a ban on assembling. Tribespeople were ordered to surrender all weapons, given a curfew between 8pm and 5am, warned that all "traitors" would be killed, and instructed to inform on all "apostates" in the group — defined as anyone who fights IS.
The Syrian Observatory estimates that 900 members of the al-Shaitaat tribe have been killed by IS to date.
The UN report also contains some other chilling details about the punishments inflicted on individuals or groups of people perceived to be a threat to the leadership of IS, also known as ISIS.
"ISIS employs the practice of takfir, declaring someone to be a heretic, in order to justify attacks on any individual or group it perceives to be a challenge to its dominance," it states.
"The mutilated bodies of male victims are often placed on display, a warning to the local population of the consequences of failure to submit to the armed group's authority."
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