Lavrenty Beria was the Soviet Secret Police Chief from 1938 until 1953.
On 30 July 1939 he became a member of Stalin's State Defence Committee (NKVD) and kept Stalin informed of Armed Forces' movements.
He kept dossiers on generals and threatened to discredit some of them, for example General Malinovsky.
The NKVD, under Beria, was responsible for the deportations in Poland and the Baltic States.
From 1943 to 1945 the NKVD carried out deportations of Crimean Tartars and other minority nationalities.
Another of his duties was to control Soviet partisans behind German lines and POW camps, which were under the jurisdiction of Smersh.