The family of the first Russian soldier confirmed dead in Syria buried their son in a village graveyard yesterday, with his father saying there were no signs on the body to support the official account he had hanged himself.

Russian defence officials say Vadim Kostenko, 19, hanged himself at a base on the Syrian coast on Saturday because of problems in his personal life. His body was handed over to his parents on Tuesday, making him the first confirmed military fatality of Russia’s four-week-old bombing campaign.

“There were no marks on his body to suggest that he had hanged himself,” Vadim’s father, Alexander, told Reuters after his son’s funeral in southern Russia. The circumstances of the air force technician’s death have aroused suspicion in Russia, where Kremlin critics accuse the authorities of hiding the truth of military casualties in other conflicts, especially in Ukraine where Moscow denies its forces have fought despite what the West says is overwhelming evidence.

Mr Vadim’s parents, Alexander and Svetlana, say their son had sounded cheerful over the phone when they spoke to him the day he died, which led them to doubt that he hanged himself.

Novaya Gazeta newspaper quoted an unidentified uncle as saying Mr Kostenko’s body bore wounds inconsistent with hanging.

“He had a broken jaw and the back of his head was bashed in. And his neck was broken,” the uncle was quoted as saying. He also said his nephew’s nose was broken.