Within the 1991 Yugoslav campaign in Croatia, the 5th (Banja Luka) Corps of the Yugoslav People's Army ("Jugoslovenska Narodna Armija" – JNA) was tasked with advancing north through the Western Slavonia region, from Okučani to Daruvar and Virovitica, and with a secondary drive from Okučani towards Kutina. This task was essentially consistent with the line expected to be reached by the main thrust of the JNA advancing from the Eastern Slavonia in about a week. The linkup was designed to facilitate a further advance west to Zagreb and Varaždin. The Corps had already deployed a battlegroup of the 265th Mechanised Brigade near Okučani to support the advance that started on 21 September, and reached the Papuk Mountains. The corps received two motorised and one artillery brigades as reinforcements during the advance, but the problems with morale and desertions experienced by the JNA elsewhere were also present in the Banja Luka Corps.