A top Russian security official said in an article published on Friday that Moscow had "neutralized" hundreds of foreign spies in recent years.
Nikolai Patrushev, the secretary of Russia's Security Council, wrote in Russia's foreign intelligence agency's house magazine:
"In recent years, hundreds of employees of foreign intelligence services, as well as other persons involved in organizing intelligence and subversive activities against our country and our strategic partners, have been identified and neutralized."
Patrushev, a close ally of Russian President Vladimir Putin, is a former director of the Federal Security Service (FSB) and is seen as a key advocate of hardline, hawkish policies within the Kremlin.