his own rank-and-file, Drenović formally participated in the attack, but he was able to prevent its success through allowing the Italians to move past his battalion and attack the Partisan rear. According to Partisan sources, he forewarned the Italians and Ustaše, and divulged the Partisan plan to them. Alliance with the NDH In response to highly effective pro-Chetnik agitation from within, many Partisan units defected to the Chetniks. In the second half of April 1942, the Partisans responded with aggressive military action against the defectors. The unit that led this offensive was the Grmeč Shock Anti-Chetnik Battalion, formed earlier that month from wholly loyal and reliable troops. This offensive spelt the end of Drenović's "Petar Kočić" Chetnik Detachment, and Drenović took refuge with the Ustaše in Mrkonjić Grad. On 27 April, he and other defeated Chetnik commanders signed an agreement with the NDH. The agreement had eight points, which included requiring that hostilities between the Ustaše and Drenović's Chetniks come to an end, that the NDH forces protect Serb villages from the Partisans, and that the Ustaše units assist the Chetniks in fighting the Partisans. The agreement also required the Ustaše to restore religious and civil rights to Serbs of the Krajina. In turn, Drenović issued a declaration in which he recognised the sovereignty of the NDH. Historian Enver Redžić argues the agreement was reached out of military and political necessity. He writes: The NDH authorities considered that the alliance would also mean that the Chetniks could continue to subvert Partisan units. On 30 April, the NDH authorities recognised the rights of Drenović and his troops to remain armed in order to fight the Partisans. The agreement between the NDH and Drenović's Chetniks was soon made public by the Ustaše press; Serb public opinion remained divided. By May, Drenović had a force of about 350 Chetniks. Around mid-month, he signed an agreement with a Croatian general staff officer in Banja Luka agreeing to cooperate with the NDH in fighting the Partisans. Drenović soon emerged as one of the most important Chetnik leaders in western Bosnia. That summer, when order had been established in significant parts of the Italian occupation zone, Drenović and other Chetnik detachment leaders and their principal political spokesmen with Italian Second Army headquarters were recognised by the Italians as auxiliaries. Early in the summer the Second Army commander, Generale designato d'armata (acting General) Mario Roatta, allowed for