On September 10, 1939, the "Einsatzgruppe V" entered the town to commit various crimes against the populace. It immediately carried out mass searches of Polish offices, courts and organizations, arrested dozens of Poles, and expelled 70 Jews. The German police established a prison for Poles in the town, and a special court. In October and November 1939, the Germans executed 11 Poles at the local cemetery. Families of the victims were expelled to the so-called General Government. Local teachers and school principals were among Polish teachers and principals murdered in the Mauthausen concentration camp. 18 Poles from the town and county were murdered by the Russians in the Katyn massacre in 1940, including pre-war starosta Zygmunt Młot-Przepałkowski and the chief of the local police Zygmunt Pampuch. On December 3-4, 1940, the German gendarmerie expelled around 500 Poles, including old, ill and disabled people, who were then held for several days in a camp in Działdowo and afterwards deported in freight trains to the Kraków District of the General Government. A penal "education" forced labour camp was operated in the town from 1941 to 1943. There was a high death rate in the camp due to hunger, diseases, tortures and executions.