before the invasion took place Polish police conducted several arrests during which they found explosives, armbands and guns. During the night between 2 and 3 September a number of German saboteurs dressed up in Polish uniforms woke up inhabitants of two districts in Bydgoszcz telling them to run as Poland has been defeated, and as a result a significant number of civilians panicked and started fleeing the city. The chaotic flight disrupted and restricted movements of the Polish military on the roads. By the morning of 3 September a certain few Germans who were in good relationship with their Polish neighbors started warning them to hide as "something bad will happen in the city", offering them shelter under the condition that they must hide by 10 AM, but stated they could not disclose details on what would take place. As a contingent of the Polish Army (Army Pomorze's 9th, 15th, and 27th Infantry Division) was withdrawing through Bydgoszcz it was attacked by German irregulars from within the city. According to a British witness, a retreating Polish artillery unit was shot at by Germans from within a house; the Poles returned fire and were subsequently shot at from a Jesuit church. In the ensuing fight both sides suffered some casualties; captured German nonuniformed armed insurgents were executed on the spot and some mob lynching was also reported. A Polish investigation concluded in 2004 that Polish troops had been shot at by members of the German minority and German military intelligence (Abwehr) agents; around 40–50 Poles and between 100 and 300 Germans were killed. German propaganda Goebbels' Propaganda Ministry heavily exploited the events to try to gain support in Germany for the invasion. As British historian Ian Kershaw wrote: Hitler's secret decree of 4 October 1939 stated that all crimes committed by the Germans between 1 September 1939 and 4 October 1939 were not to be prosecuted. The Wehrmacht War Crimes Bureau investigation in 1939–1940 claimed that the events were a result of panic and confusion among the Polish troops. The Wehrmacht investigation included the interrogation of captive Polish soldiers, ethnic Germans from Bydgoszcz and surrounding villages, and Polish civilians. The bodies of the victims were exhumed and the cause of death and the possible involvement of military rifles was assessed. German reprisals and atrocities The events were followed by German reprisals and mass executions of Polish civilians. In an act of