A Russian police officer was convicted today on charges of spying for the US using a cache disguised as a rock and sentenced to 15 years in prison.
It was the latest in a host of spy cases amid rising Russia-West tensions over Ukraine.
The Moscow City Court today found Roman Ushakov guilty of treason for handing over classified information to the United States. Prosecutors produced his messages, which contained sensitive information about the Interior Ministry, as well as a rock-like cache with cash and a letter from the CIA, according to the Interfax news agency.
Interfax quoted prosecutor Viktor Antipov as saying Ushakov was caught red-handed, pleaded guilty and gave detailed testimony about his contacts with US intelligence.
Antipov said Ushakov worked in Siberia, but gave no further details.
The court said Ushakov was arrested in 2013 while trying to open the cache, which contained USD 37,000 for his information and a letter from the CIA with further instructions.
It's not the first time a rock-like cache has emerged in a spy case. In 2006, Russia accused four British diplomats of espionage, saying they received secret information from a radio transmitter hidden in a rock.
There has been a spike in the number of spy cases in the past year as Russia-West relations have plunged to their lowest point since the Cold war times.
The United States and the European Union have slapped Russia with sanctions over its annexation of Ukraine's Crimean Peninsula and its support for a separatist insurgency in eastern Ukraine. Moscow denies the charges.
In January, a Russian mother of seven was arrested at her home in the western town of Vyazma on charges of treason. Svetlana Davydova was accused of calling the Ukrainian Embassy after she had overheard a serviceman saying he and his comrades were preparing for a trip and decided he was talking about being sent to Ukraine.
She was freed last month but charges against her are still pending.
In other cases, Yevgeny Petrin, who worked with the Russian Orthodox Church's external relations department, was put behind bars on charges of spying for the US; Vladimir Golubev, a former nuclear researcher; has been accused of divulging secrets in a scientific article; and Pyotr Parpulov, an air traffic controller in Sochi, the Black Sea resort that hosted 2014 Winter Games, was jailed on espionage charges after the games ended.
