Former US marine Paul Whelan was convicted of espionage and sentenced to 16 years in prison.

Whelan was also an Irish, British and Canadian citizen who was detained at a Moscow hotel in December 2018 by Russian authorities who alleged he was involved in an intelligence operation.

He has been in Lefortovo prison in Moscow since, and the trial was held behind closed doors.

His lawyer, Vladimir Zherebenkov, previously said Whelan was unwittingly handed a flash drive containing “state secrets” while on a personal trip to Russia.

Russian Foreign Minister Sergey Lavrov has said Whelan was caught “red-handed.”

Whelan denies the spying charges and says he has been denied proper medical treatment while in detention.

His family maintains he traveled to Moscow to attend a wedding and was arrested on false charges.