A Syrian asylum seeker has been sentenced to life in prison by an Austrian court after being convicted of war crimes for killing 20 wounded government soldiers in his country’s civil war.

The 27-year-old, who has not been named, was found guilty of 20 charges of “murder as a terror offense” by a jury in Innsbruck late Wednesday. The accused denies the charges.

His case first came to the attention of authorities after he allegedly told other refugees at a shelter in Tyrol that he had killed unarmed or injured regime soldiers in the Syrian province of Homs in 2013 and 2014, according to Austrian media reports. The man allegedly said he had belonged to a rebel brigade affiliated with the Free Syrian Army — the country’s main armed opposition group in the early days of the conflict.

Killing injured soldiers is a war crime under the Geneva Conventions.

An interpreter told the court the man had described the killings to him in Arabic. The asylum seeker later claimed his testimony had been mistranslated and denied the killings, but the interpreter contradicted him in court, saying: “The defendant told me he had shot badly wounded soldiers. I asked him to repeat his claim and he did.”

The man, a stateless Palestinian who grew up in a refugee camp in Homs, plans to appeal the ruling, according to his lawyer.

The case is believed to be the first time Syrian war crimes have been tried in Austria. The country’s courts have previously jailed people for belonging to terrorist organizations, such as ISIS, involved in Syria’s fractured six-year conflict.

Austria could not extradite the man due to the ongoing civil war in his homeland.