Poland. During the interbellum the city witnessed not only Anti-Polish, but also Anti-French incidents and violence by the Germans. In 1920, local Polish doctor and city councillor , protested against the German refusal to treat French soldiers stationed in the city. In January 1922, he himself treated French soldiers shot in the city. On 9 April 1922, 17 Frenchmen died in an explosion during the liquidation of a German militia weapons warehouse in the present-day Sośnica district. Styczyński, who defended the rights of local Poles and protested against German acts of violence against Poles, was himself murdered by a German radical/militant on 18 April 1922. Nevertheless, various Polish organizations and enterprises still operated in the city in the interbellum, including a local branch of the Union of Poles in Germany, Polish banks and a scout troop. On 9 June 1933, Gliwice was the site of the first conference of the Nazi anti-Polish organization Bund Deutscher Osten in Upper Silesia. In a secret Sicherheitsdienst report from 1934, Gliwice was named one of the main centers of the Polish movement in western Upper Silesia. Polish activists were increasingly persecuted starting in 1937. An attack on a radio station in Gleiwitz on 31 August 1939, staged by the German secret police, served as a pretext, devised by Reinhard Heydrich under orders from Hitler, for Nazi Germany to invade Poland, which marked the start of the Second World War. Shortly after the outbreak of World War II, on 4 September 1939, the Einsatzgruppe I entered the city to commit atrocities against Poles. After the invasion of Poland, the assets of local Polish banks were confiscated by Germany. The Germans 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. During the war, the Germans operated a Nazi prison in the city, and established numerous forced labour camps, including a Polenlager camp solely for Poles, a camp solely for Jews, a penal "education" camp, a subcamp of the prison in Strzelce Opolskie, and six subcamps of the Stalag VIII-B/344 prisoner of war camp. From July 1944 to January 1945, Gliwice was the location of four subcamps of the Auschwitz concentration camp. In the largest subcamp, whose prisoners were mainly Poles, Jews and Russians, nearly 100 either died of hunger, mistreatment and exhaustion or were murdered. During the evacuation of another