In 1951 and 1952, with the Korean War as a background, a congressional investigation chaired by Rep. Ray Madden and known as the Madden Committee investigated the Katyn massacre.
In the Soviet Union during the 1950s, the head of KGB, Alexander Shelepin, proposed and carried out the destruction of many documents related to the Katyn massacre in order to minimize the chance that the truth would be revealed [REF].