Three advocacy groups have filed a criminal complaint against Russian private military contractor Wagner Group over the torture and death of a detainee in Syria’s civil war.

"This litigation is a first-ever attempt by the family of a Syrian victim to hold Russian suspects accountable for serious crimes committed in Syria," the Paris-based International Federation for Human Rights, the Syrian Center for Media and Freedom of Expression and the Russian group Memorial said in a joint statement on Monday, which noted that Russian law allows the state to investigate crimes committed by Russian citizens abroad.

The criminal complaint filed in Moscow alleges that six Russian mercenary soldiers took part in the 2017 killing of Muhammad “Hamdi Bouta” Taha al-Abdullah in Syria’s Homs governorate.

Originally from Syria's eastern province of Deir ez-Zor, Abdullah had fled to neighboring Lebanon during the civil war, but upon his return to Syria in 2018 he was arrested and forcibly conscripted into the Syrian army. He reportedly defected and was then captured by the Russian paramilitaries.