In a report released on Monday, the HRW urged authorities to remove the human remains from the al-Hota gorge located 85 kilometers (53 miles) north of Raqqah city and preserve the evidence for criminal proceedings against the murderers.
By flying a camera-equipped drone into the 50-meter-deep gorge, the rights group discovered the remains of at least six people floating at the bottom.
Based on the state of decomposition, the HRW said, the bodies were dumped there long after Daesh had left the area. The identities of those victims and their causes of death remain unknown.
According to the report, geological maps and a 3D topographic model of al-Hota from the drone imagery suggest that the gorge goes deeper than the drone was able to see; therefore, more human remains may lie below the water’s surface.
“Al-Hota gorge, once a beautiful natural site, has become a place of horror and reckoning,” Sara Kayyali, Syria researcher at HRW said.
“Exposing what happened there, and at the other mass graves in Syria, is crucial to determining what happened to the thousands of the people ISIS [Daesh] executed and holding their killers to account,” she said referring to the terror group.
The HRW investigation also involved interviews with local residents and a review of Daesh recorded videos in addition to the analysis of satellite imagery.
Locals recalled that when Daesh controlled the Raqqah area, its members threatened people with being thrown into al-Hota. Some said they saw bodies scattered along the gorge’s edge.
One man who had gone to collect desert truffles that grow in the area in March 2015 said he saw a body stuck on a protruding ledge.
“This was a dumping area for bodies from all over,” he told HRW. “They [Daesh terrorists] brought them in from Raqqah, Dayr al-Zawr — nobody knows how many bodies were there.”
A Daesh-recorded video posted on Facebook in 2014 showed a group of men throwing two bodies into the gorge.
The clothes on the men matched those worn by two people shown in another video being executed by the terrorists.
More than 20 mass graves containing thousands of bodies have been found in areas formerly held by Daesh in Syria, the HRW said.
However, efforts to exhume these mass graves have been faltering due to a fluid security situation, limited resources and minimal outside support, it said.
The al-Hota gorge is currently controlled by Turkish-backed militants, while Raqqah city remains under the control of the Kurdish-led militants supported by the US. The two anti-Damascus parties are engaged in a conflict in the northern parts of Syria.
Kayyali said those in control of the gorge “should facilitate the collection of evidence to hold ISIS members accountable for their horrendous crimes, as well as those who dumped bodies in al-Hota before or after the ISIS [Daesh] rule.”
Many believe that the US created the Daesh terrorist group and helped it rise and commence its reign of terror and destruction in Syria and Iraq in 2014.
Daesh has already been driven out of all its urban bastions both in Iraq and Syria, but its remnants carry out sporadic terror attacks in both neighboring Arab countries.