The bombing of Wieluń is considered by many to be the first major act of World War II, and the September Campaign. After Luftwaffe air units moved into Polish airspace in the early morning of 1 September, they reached the town of Wieluń by 04:40–45 hours. Around this time, the first strikes on the town were conducted, with a total of 46,000 kg bombs being dropped on civilian targets for 9 consecutive hours. Elsewhere, the Battle of Westerplatte and Danzig skirmishes began around the same time (04:45 h), starting the well-coordinated Invasion of Poland. Located near the German border, the town of Wieluń was completely undefended, lacking anti-air capabilities and a military garrison. Despite Wieluń having no military targets, airstrikes continued. German intelligence reports had stated there was a Polish cavalry brigade stationed in the town. The Luftwaffe bombed the nearby towns of Działoszyn, Radomsko, and Sulejów, which also had no military targets. The attack on the town has been described as the first war crime committed by Germany in World War II. The Luftwaffe had reportedly bombed a "clearly marked" hospital, and strafed fleeing civilians. In the aftermath, 127 civilian casualties were reported – possibly "several hundred" – but the exact number remains unknown. 70% of the town (90 percent, in the city center) was destroyed. Timing The exact time the first bombs fell on Wieluń on the morning of 1 September 1939 has been a subject of debate, particularly in reference to claims that the town's bombing was the first overt act of World War II, preceding by five minutes the shelling of Westerplatte at 04:45, which has traditionally been considered the opening of the war. The time given by most Polish sources is 04:40, but this is an average of eyewitness reports on various phases of the initial bombing run, which likely lasted more than a minute. Polish historian Tadeusz Olejnik reports a number of accounts of the first bombs falling as early as 04:30. Another Polish historian, Jan Książek, described 04:40 as a "certainly confirmed" time. German sources report the time as 05:40, based on German flight documents (Startzeit: 5.02, Angriffzeit: 5.40, Landezeit: 06.05: take-off 05:02, attack 05:40, landing 06:05). The time difference, 04:40 versus 05:40, has been attributed by several writers, such as journalist , to a summer time-difference between Poland and Germany. Other historians, such as Grzegorz Bębnik, disagree that there was a time