The Islamic State (ISIS/ISIL) used an ancient Roman amphitheater in Syria’s historic city of Palmyra for a mass execution of prisoners, forcing civilians to watch, according to a watchdog group.
Civilians trapped in Palmyra were rounded up by ISIS and forced to watch as the jihadist group executed a group of twenty men accused of fighting on behalf of Syrian Dictator Bashar al-Assad, reports the U.K.-based Syrian Observatory for Human Rights (SOHR), which monitors the Syrian conflict using a network of sources on the ground.
The men were shot dead, according to the observatory.
Palmyra, home to a UNESCO World Heritage site, was captured by ISIS last week. Some analysts worry that the jihadist group will loot and destroy the 2,000-year-old monuments and ruins in the city.
“Thousands of Palmyra’s residents fled but many are still living within the city walls, while the UN human rights office in Geneva said it had received reports of Syrian government forces preventing people from leaving until they retreated from the city,” reports The Independent.
On Wednesday, ISIS released a video showing that all of the ancient sites in Palmyra remain intact, for now.
According to SOHR, ISIS has killed at least 67 civilians, including 14 children and 12 women, in the city of al-Sikhni, the village of al-Aamiriyyi, and in Palmyra for “dealing with the regime forces and hiding regime’s members in their houses.”
In total, ISIS has killed at least 237 people since May 16, including dozens of civilians, women, children, and members of the Assad regime, the monitor said.
ISIS is holding “about 600 prisoners of the regime forces, allied militiamen and civilians accused of being ‘agents for the regime,'” it added.
ISIS currently controls more than half of Syria, including all the country’s border crossings with Iraq.