 In October 1941, German soldiers conducted two mass murder campaigns against Serbian civilians in Kraljevo and Kragujevac, with a combined death toll reaching over 4,500 civilians, convincing Chetnik leader Draža Mihailović that killing German troops would only result in further unnecessary deaths of tens of thousands of Serbs.As a result, he decided to scale back Chetnik guerrilla attacks and wait for an Allied landing in the Balkans.While Chetnik collaboration reached "extensive and systematic" proportions, the Chetniks themselves referred to their policy of collaboration as "using the enemy".