The Soviet Union occupied Pinsk after the Nazi-Soviet Pact divided Poland in 1939. Świątek was arrested by the NKVD in April 1941, and held on death row in Brest for two months. Father Świątek escaped from prison, taking advantage of the confusion caused by the Nazi German invasion of the Soviet Union on 22 June 1941, and returned to Pruzhany. In December 1944, the NKVD arrested Swiatek for a second time. The following year he was sentenced to 10 years hard labor in a concentration camp, and spent nine years in Siberia and the north of the Soviet Union, working in the taiga and in the mines. After his release in June 1954, he returned to Pinsk.