Shortly after the outbreak of World War II, on September 4, 1939, the "Einsatzgruppe I" entered the city to commit various atrocities against Poles. After the invasion of Poland, the assets of local Polish banks were confiscated by Germany. The Germans also formed a "Kampfgruppe" unit in the city. It was also the cremation site of many of around 750 Poles murdered in Katowice in September 1939.