MOSCOW - Igor Korobov, chief of the Russian Main Intelligence Directorate, commonly known as the GRU, died at the age of 63 after a serious illness on Wednesday, the Defense Ministry said in a statement.

According to the ministry, Korobov was awarded with the Hero of the Russian Federation, the highest honorary title in the country, for his service as the intelligence agency's leader.

Korobov worked in military intelligence since 1985 and occupied different positions in the Main Intelligence Directorate. He began to run the agency in early 2016.

He also served as the deputy head of the General Staff of the Russian Armed Forces.