Дальневосточный фронт
A Red Army veteran of the Russian Civil War, Sorkin was sent to Mongolia as an artillery instructor for the Mongolian People's Army in 1923, where he later served as a consular official in Altanbulag and first secretary at the Soviet embassy in Ulan Bator in 1926-1931. The chief of the Soviet General Staff's Special Operations Department in 1939-1941, he served as intelligence chief for the Far Eastern Front in 1941-1945 and the 1st Far Eastern Front following the Soviet declaration of war on the Japanese Empire in August 1945.