Page "Bloody Sunday (1939)" Paragraph 6

According to the most widely accepted version, the incident stemmed from groups of German saboteurs attacking Polish troops behind the front lines.

This version holds that, as a contingent of the Polish Army was withdrawing through Bydgoszcz ( Army Pomorze's 9th, 15th, and 27th Infantry Division ) 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 to 300 Germans were killed.