Hundreds of unidentified bodies which seem to have been tortured have been found in a former Islamic State group stronghold, Syrian state media says.
Seven mass graves near Albu Kamal in eastern Syria have been unearthed, the official Sana news agency reports, with more than 100 bodies recovered so far.
Most seem to “have been subjected to torture and ill-treatment before execution”, Sana says.
IS has been accused of numerous atrocities in Iraq and Syria.
A Syrian Red Crescent official told AFP news agency there were several women among the dead, and said some of those killed “were blindfolded and handcuffed”.
Syria forces drove the jihadist group from Albu Kamal in Deir al-Zour province on the border with Iraq last year.
At the peak of the group’s power, about 10 million people lived in IS-controlled areas, but the US military said earlier this year that the jihadists had been ousted from 98% of their former territory.
In Syria, the group is still present in small pockets in the south and east.
Where their forces have been ousted, evidence of atrocities have been uncovered.
Last month the Associated Press reported the discovery of a mass grave containing more than 500 bodies near the northern city of Raqqa.
And following the liberation of Palmyra by Syrian troops in 2016, a mass grave containing the bodies of men, women and children was unearthed in the north-east of the city.