Largely the same groups were responsible for the mass killing operations during the civil war , collectivisation , and the Great Terror . These groups were associated with Yefim Yevdokimov ( 1891 – 1939 ) and operated in the Secret Operational Division within General State Political Administration ( OGPU ) in 1929 – 31 . Yevdokimov transferred into Communist Party administration in 1934 , when he became Party secretary for North Caucasus Krai . He appears to have continued advising Joseph Stalin and Nikolai Yezhov on security matters , and the latter relied on Yevdokimov 's former colleagues to carry out the mass killing operations that are known as the Great Terror in 1937 – 38
Great Terror
Great Purge
Ukraine