 Complete the following phrase:  Occupied by the Soviet Union following the Molotov-Ribbentrop Pact of 1939, it was subject to harsh policies of the NKVD. The uncompleted prison was taken over by the NKVD in December 1939 and was used for political prisoners from all parts of Soviet-occupied Poland. Between 1500 and 3000 prisoners were kept there in harsh conditions, with new inmates arriving after the previous ones were successively transported to Gulag and other Soviet prisons. In 1940 most of the local Poles were arrested and resettled to various Soviet Gulags and prisons throughout the USSR. In 1941, following the outbreak of 