The leader of the Russian private military company Wagner, Yevgeny Prigozhin, claimed a US citizen died in the embattled Ukrainian city of Bakhmut, in a video posted on the Wagner Telegram group on Tuesday.

A pro-Kremlin military blogger, Alexander Simonov, introduces the video saying "we are advancing to the advanced positions of the PMC Wagner in the western regions of Artyomovsk," the Russian name for Bakhmut.

The video is filmed at night with the sound of an apparent mortar attack. The soldiers shout, "Into the shelter. Mortar attacks from the western side."

Prigozhin is shown inspecting a body, and what he claims are US identification documents.

CNN cannot verify the authenticity of the documents and cannot confirm the nationality of the body shown in the video.

Prigozhin says, "So we will hand him over to the United States of America, we'll put him in a coffin, cover him with the American flag with respect because he did not die in his bed as a grandpa but he died at war and most likely a worthy [death], right?"

A soldier claims that the man was returning fire when he died. Prigozhin replies, "He was shooting back; he died in the battle, so we will hand over his documents tomorrow morning and pack everything, right?"

Prigozhin and Wagner group frequently post videos for propaganda purposes, and often mix real footage with propaganda claims. CNN has reached out to the US State Department for comment.