A Moscow court has sentenced a retired military officer to 12 years in prison after convicting him of treason, a charge that is usually linked to alleged espionage.
Retired Colonel Aleksei Sinyakov was found guilty of high treason on December 15 and sentenced the same day.
The court also ruled that Sinyakov will be stripped of his rank as a colonel.
The court did not make the details of the case public, as it was classified as Top Secret, and the trial was held behind closed doors.
Sinyakov's case is one of several in 2016 in which Russian citizens have been charged with high treason.
Russia's Supreme Court said in April that 28 people were convicted of high treason in 2015.