A U.S. citizen on Monday was ordered to serve almost seven years behind bars for allegedly fighting as a mercenary on behalf of Ukraine, Russian state media reported. Stephen Hubbard, 72, seemed to acknowledge his guilt in court documents, the Kremlin-run news agency TASS reported last month.

What’s the story with this case? Hubbard moved to Ukraine with his wife in 2014 and joined Ukraine’s armed forces without fully understanding the Kremlin’s actions, according to TASS reports. Hubbard said Russian troops treated him well when they captured him on the battlefield, according to TASS. The agency also reported that Hubbard said he now has a better understanding of why Russia was fighting in Ukraine, and is sympathetic toward Russia’s actions.

What does the United States have to say? U.S. State Department spokesman Matthew Miller expressed its disappointment over the verdict against Hubbard during a press briefing on Monday. Russian forces arrested Hubbard in Ukraine, not Russia, and he had already spent 2 years behind bars before receiving his sentence, Miller said. Miller also noted that Russia had denied Hubbard consular access despite the fact that there seemed to be no question about his American citizenship.

Dig deeper: Read Lauren Canterberry’s report about how the Kremlin has claimed control over one of Ukraine’s eastern cities after years of fighting.