World War II began for the city on 9 and 10 September 1939, when the Polish 54 light artillery regiment fought a skirmish with a German armored division. On September 10, 1939, German troops committed a massacre of 21 Polish prisoners of war in the town (see also "Nazi crimes against the Polish nation"). Afterwards, the Germans terrorized the population, and Poles over the age of 14 were subjected to forced labour. Additionally, around 400 people were captured in roundups and deported to forced labour in Germany. The Germans also committed massacres of Poles in nearby forests as part of the "AB-Aktion".