On October 31 , 1991 , Croatian forces launched Operation Otkos 10 securing the Bilogora hills . Following this success , the Croat Operation Orkan 91 , on December 12 , pushed back the Serb/Yugoslav forces into a small pocket only a fraction of the initial territory controlled . In the operation , Daruvar was taken . During their retreat , Serbian paramilitaries committed the Voćin massacre . On January 2 , 1992 , the UN brokered a ceasefire in Sarajevo , it is possible that this stopped the Croatian forces from eliminating the rebel Serb presence in Western Slavonia
Voćin massacre
Voćin massacre
SAO Western Slavonia