Soviet war hero Vasili Blokhin was hand-picked by Stalin — to serve as chief executioner of the NKVD:
Blokhin is recorded as having personally executed tens of thousands of prisoners by his own hand, including the notorious Katyn Massacre of 7,000 Polish officers (each night 250 men were shot one by one, over a month’s time)[2][3]—making him the most prolific official executioner in recorded world history. He was awarded both the Order of the Badge of Honor (1937) and the Order of the Red Banner (1941).
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Blokhin was forcibly retired following Stalin’s death, although his “irreproachable service” was publicly noted by Lavrenty Beria at the time of his departure. After Beria’s fall from power (June 1953), Blokhin’s rank was eventually stripped from him in the de-Stalinization campaigns of Nikita Khrushchev. He reportedly sank into alcoholism, went insane, and died February 3, 1955 with the official cause of death listed as “suicide”.