Robert Patrick Hoffman II, who was a cryptologic technician in the U.S. Navy, attempted to spy on behalf of the Russian Federation. He attempted to hand over classified documents to undercover FBI agents posing as Russian operatives in 2012. In December of 2012, Hoffman was arrested by FBI and NCIS agents. He was sentenced to 30 years in prison for attempting to commit espionage against the United States.
(From: https://archives.fbi.gov/archives/norfolk/press-releases/2014/former-sailor-sentenced-to-30-years-in-prison-for-attempted-espionage)
Court of Appeals, 26 Mar 2015.