[ O.S. May 31] 1898, Kiev – February 2, 1940 or June 4, 1942, Moscow), born Mikhail Efimovich Fridlyand (Friedland) (Михаил Ефимович Фридлянд), was a Soviet journalist. Koltsov was the son of a Jewish shoemaker and the brother of Boris Efimov . Koltsov participated in the Russian Revolution of 1917 ,