Two boys under the age of 18 were crucified by ISIS in the streets of the Syrian city of al-Mayadin for not observing the laws of Ramadan, watchdog group the Syrian Observatory for Human Rights reported on Monday.

The children, who were charged with the crime of “not fasting on Ramadan,” had placards around their necks announcing their crime was committed “with no religious justification,” The Independent reported. 

Founder of the watchdog group, Rami Abdel Rahma, told The Independent  that the boys had reportedly been caught eating, and their bodies were found “hanging on crossbars” near the ISIS police headquarters.  The boys were reportedly hung from their wrists, and their bodies were left on display until late Monday evening.

This is not the first time ISIS has crucified its citizens for breaking Sharia law.

A UN Committee on the Rights of the Child report exposed “several cases of mass executions of boys, as well as reports of beheadings, crucifixions of children and burying children alive.”

In May, Islamic State militants in Libya crucified three brothers of a local family after suspicions arose that they were supporting the local Libyan government, which under ISIS law is equivalent to apostasy.

“We are really deeply concerned at torture and murder of children,”  UN Committee on the Rights of the Child member Renate Winter was quoted as saying.  “The scope of the problem is huge.”

Ariel Cohen and Reuters contributed to this report.