Human Rights Watch has published a report, based on witness statements, supporting the claims of the deaths of thousands of detainees in Syria’s prisons.

HRW interviewed four former inmates from the Sednaya Prison in Damascus. All said they witnessed the death of fellow detainees following beatings, torture, malnutrition, and disease.

The witnesses described overcrowding, lack of food, inadequate heating and ventilation, poor medical services, and extremely poor sanitary conditions. All said they had lost significant weight during their detention, with one losing more than half and weighing only 50 kilograms (110 pounds) when he was released.

In January, a panel of senior international lawyers and forensic experts published a report concluding that Syrian authorities had committed systematic torture and killing of detainees. The report was based on 55,000 photographs by a military defector, “Caesar”, that documented an estimated 11,000 deaths. The bodies showed signs of starvation, brutal beatings, strangulation, and other forms of torture and killing.

Two of the former detainees said they had seen bodies being taken from Sednaya Prison to the Tishreen military hospital in northern Damascus.

On May 22, the UN Security Council voted on whether to refer the situation in Syria to the International Criminal Court (ICC), in part because of the allegations of mass deaths in detention. Russia and China vetoed the resolution.