A Russian court has sentenced a 72-year-old American citizen to almost seven years in jail for allegedly fighting as a mercenary for Ukraine.

Prosecutors said Stephen James Hubbard was serving in a defence unit based in the eastern city of Izyum when he was captured by Russian forces in April 2022, shortly after Moscow launched its full-scale invasion of Ukraine.

Hubbard “systematically received material compensation” for his participation in the war on the Ukrainian side, a statement by the Russian Prosecutor General said.

He has now been sentenced to 6 years and 10 months imprisonment in a penal colony.

Hubbard, a native of Michigan, pleaded guilty to the charges last week, according to Russian state media.

However, his sister Patricia Fox told Reuters that Hubbard held pro-Russian views and was unlikely to have taken up arms at his age.

“He is so non-military,” Ms Fox told Reuters, adding that her brother “never had a gun, owned a gun, done any of that… He’s more of a pacifist.”

According to Ms Fox, Hubbard had moved to Ukraine in 2014 and lived there for a time with a woman, surviving off a small pension. He and his partner later split but he continued living in Ukraine.

Although Hubbard was detained by Russian forces in early 2022, his case only became public when his trial began in Moscow in September.

In a video shared by Russian authorities, Hubbard can be seen walking with difficulty inside the defendants’ glass box in the courtroom where he was sentenced on Monday.

The eastern Ukrainian city of Izyum where Hubbard was detained was captured by Russia soon after it invaded Ukraine. It was liberated by Ukrainian troops in the autumn of 2022.

In a separate case, on Monday Robert Gilman, an ex-US marine who was already serving time in Russia for an assault conviction, was handed seven years and one month in jail for assaulting a prison officer.

At least 10 US nationals are currently behind bars in Russia. A number of Americans were released in a prisoner swap between Moscow and the West in August.