A German report stated: "The executions in Kragujevac occurred although there had been no attacks on members of the Wehrmacht in this city, for the reason that not enough hostages could be found elsewhere." Even some German informants were inadvertently killed. "Clearly", the Holocaust historian Mark Levene writes, "Germans in uniform were not that particular about who they shot in reprisal, especially in the Balkans, where the populace were deemed subhuman." Victims of the mass executions included Serbs, Jews, Romani people, Muslims, Macedonians, Slovenes and members of other nationalities. Following the massacre, the Wehrmacht held a military parade through the city centre. On 31 October, Böhme sent a report to the acting Wehrmacht commander in Southeast Europe, General der Pioniere (Lieutenant General) Walter Kuntze, reporting that 2,300 hostages had been shot in Kragujevac. Aftermath Response The Partisan commander and later historian Milovan Djilas recalled in his memoirs how the Kragujevac massacre gripped all of Serbia in "deathly horror". Throughout the war, local collaborators pressured the Germans to implement stringent vetting procedures to ensure that "innocent civilians" were not executed, though only when the hostages were ethnic Serbs. The scale of the massacres in Kragujevac and Kraljevo resulted in no quarter being given to German POWs by the guerrillas. "The enemy changed his attitude toward German prisoners," one senior Wehrmacht officer reported. "They are now usually being maltreated and shot." By the time Böhme was relieved as Plenipotentiary Commanding General in December 1941, between 20,000 and 30,000 civilians had been killed in German reprisal shootings. The ratio of 100 executions for each soldier killed and 50 executions for each soldier wounded was reduced by half in February 1943, and removed altogether later in the year. Henceforth, each individual execution had to be approved by Special Envoy Hermann Neubacher. The massacres in Kragujevac and Kraljevo caused German military commanders in Serbia to question the efficacy of such killings, as they pushed thousands of Serbs into the hands of anti-German guerrillas. In Kraljevo, the entire Serbian workforce of an airplane factory producing armaments for the Germans was shot. This helped convince the OKW that arbitrary shootings of Serbs not only incurred a significant political cost but were also counterproductive. The killings at Kragujevac and Kraljevo exacerbated tensions between the Partisans and Chetniks. They also convinced Mihailović that active resistance was futile for as long as the Germans held an unassailable military advantage in