Under his tenure the GRU has become a byword for Russian meddling in Western affairs The ministry said he died on Wednesday after a “long and serious illness” Moscow: Russia’s military intelligence chief who oversaw a series of notorious operations abroad has died after a long illness, with Moscow praising him Thursday as a “great man” and a patriot. Igor Korobov, 62, had headed the defense ministry’s Main Intelligence Directorate (GRU) since 2016 and was the target of US sanctions. Under his tenure the GRU has become a byword for Russian meddling in Western affairs. The ministry said he died on Wednesday after a “long and serious illness,” with analysts suggesting it was a code word for cancer. Korobov’s 57-year-old first deputy, Vice Admiral Igor Kostyukov, has been appointed acting GRU chief and is likely become his successor, state news agency TASS said, citing a military source. President Vladimir Putin has expressed condolences, said his spokesman Dmitry Peskov, adding the two “had been in constant dialogue.” “The dear memory of this great man, a faithful Russian son and a patriot of the Motherland... will remain forever in our hearts,” the defense ministry said. Sergei Naryshkin, the head of the SVR foreign intelligence agency, a GRU rival, praised Korobov as a “true comrade-in-arms.” The West has accused the ultra-secretive agency of carrying out attacks on foreign soil, including the poisoning of former Russian spy Sergei Skripal and his daughter Yulia with a Soviet-designed nerve agent in Britain in March. Washington has said the GRU was directly involved in interfering in the 2016 US election through “cyber-enabled activities,” while the Netherlands has said they had thwarted a GRU cyberattack on the global chemical weapons watchdog. Russia has denied the charges. Korobov did not participate in a gala marking the centenary of the service in early November when Putin heaped praise on the GRU. Korobov’s first deputy Kostyukov, who is thought to be in charge of Russia’s Syria operations at the GRU, reportedly presided over the ceremony. “If he is appointed, then he will be the first naval seaman in the history of the GRU to become a military intelligence chief,” TASS quoted its source as saying. Korobov, who joined military intelligence in 1985, received the Hero of Russia decoration for his service.