In 1939, following the Soviet invasion of Poland, Żółkiew, together with the rest of Poland's Kresy Wschodnie, was occupied by the Soviet Union. The Soviets destroyed the statue of King John III Sobieski, located in front of the town hall and the statue of the city founder hetman Stanisław Żółkiewski, located in the park. In June 1941, the Soviets executed 34 people, Ukrainians and Poles, in a prison organized in the former Żółkiewski castle, as part of the NKVD prisoner massacres. A few people managed to escape the massacre, including a German prisoner of war.