the struggle against the Communist danger" and eventually grew to consist of 3,500 armed men. These appeals failed to mention guerrilla leader Draža Mihailović or his Chetniks. By November, Ljotić was openly denouncing Mihailović. In one newspaper article, he accused him of being responsible for the deaths of many Serbs and for causing widespread destruction as a result of his "naïve" cooperation with the Communists. In direct response to the Communist uprising, the Germans decreed that 100 Serbian civilians would be executed for every German soldier killed and 50 would be executed for every German soldier wounded. This policy culminated in the Kragujevac massacre of October 1941, in which a division of Ljotić's volunteers was involved. Earlier that month, the Chetniks and Partisans had ambushed a column of German soldiers near Gornji Milanovac, killing 10 and wounding 26. The Germans turned to Kragujevac for retaliation, not because of anti-German activity in the town but because not enough adult males could be found otherwise to meet the required quota for executions. According to eyewitnesses, SDO commander Marisav Petrović and his men entered barracks in which hostages were being held and, with German approval, freed those whom they recognized as supporters of Ljotić and Nedić, as well as those whose political attitudes they considered to be "nationally correct". Petrović accused those whom he had failed to free of supporting the Communists and spreading Communist propaganda, thus "infecting" Serbian society with their leftist ideas. Most of those who remained in German hands and were subsequently executed were high school students. According to the post-war testimony of Kosta Mušicki, another high-ranking SDO commander, Petrović also ordered the arrests of countless Romani civilians from surrounding villages and handed them over to the Germans for execution. More than 3,000 citizens of Kragujevac were killed during the massacre. Serbian Volunteer Corps and propaganda efforts On 22 October, the Grand Anti-Masonic Exhibition opened in Belgrade, organized by Zbor with German financial support. The exhibition sought to expose an alleged Judeo-Masonic/Communist conspiracy for world domination through several displays featuring anti-Semitic propaganda. Serbian collaborationist newspapers such as Obnova (Renewal) and Naša Borba (Our Struggle) wrote positively of the exhibit, declaring Jews to be "the ancient enemies of the Serbian people" and that "Serbs should not wait for the Germans to begin the extermination of the Jews." The latter newspaper, Naša Borba, had been established by Ljotić earlier in the year