On October 31, 1991, an assault on local Territorial Defense (TO) units in Grubišno Polje marked the beginning of a military-police operation by Croatian forces codenamed “Otkos-10”. The objective of this operation was to establish control over the region of Eastern Bilogora, located in northwestern Croatia within the triangle formed by Bjelovar, Daruvar, and Virovitica.
Confronted by significantly larger Croatian formations supported by armored-mechanized units and artillery, the Serb population of the region began a mass withdrawal. Over the course of October 31 and the following day, the entire population of 23 villages, along with residents from 15 neighboring settlements, abandoned their homes. A refugee convoy comprising approximately 4,000 people and more than 600 vehicles crossed into the territory of Bosnia and Herzegovina. Among the displaced individuals were around 250 persons of other ethnicities (including Croats, Czechs, Hungarians, and Roma), most of whom were members of mixed families.
Following the departure of the Serb population, documented incidents occurred involving the killing of remaining civilians, alongside systematic looting, arson, and the demolition of houses by explosives—even in areas where no prior military resistance had taken place. These actions also resulted in the destruction of prominent Serbian Orthodox churches that were recognized as unique cultural monuments protected by UNESCO. Traditional wooden churches built in the specific Bilogora architectural style were burned to the ground, including the Church of St. Demetrius in Rastovac (built before 1700) and the Church of the Dormition of the Most Holy Mother of God in Donja Rašenica (built in 1709).
Between 1991 and 1997, a total of 64 individuals lost their lives in the region of Eastern Bilogora, the majority of whom were of Serb ethnicity or related to Serb families. Among the casualties were 41 civilians—18 of whom were killed prior to Operation “Otkos-10” during a campaign of intimidation—and 21 members of the Territorial Defense. Out of the total number of victims, the search continues for the mortal remains of 16 individuals.
To date, the only individual prosecuted before judicial authorities for the crimes committed against Serbs in Eastern Bilogora is Veljko Marić, a former member of the Croatian National Guard (ZNG) from Grubišno Polje. The War Crimes Chamber in Belgrade sentenced him to 12 years in prison for the war crime against civilians, specifically for the murder of Petar Slijepčević (born 1926), who was shot and killed in his family home in the village of Rastovac on October 31, 1991.
While serving his sentence, Serbian judicial authorities initiated a new investigation against Marić on suspicion of executing Mićo Vasiljević and Vladimir Kučera, and the unlawful detention and torture of Zvjezdan Mačak in September 1991. In June 2015, prior to the conclusion of this investigation, Marić was transferred to Croatia under an official commitment by the Croatian authorities to continue the criminal proceedings initiated in Serbia. To date, there has been no official confirmation that Croatian judicial bodies have fulfilled this obligation. Conversely, in March 2016, the Municipal Court in Bjelovar issued a legally binding ruling awarding approximately 50,000 EUR in damages and 7,000 EUR in legal fees to the wife and son of the victim, Petar Slijepčević.
The demographic consequences of these events are profound. Prior to World War II, approximately 18,000 residents of Serb ethnicity lived in the Eastern Bilogora region. According to data from the Metropolitanate of Zagreb and Ljubljana, by 2005 only 1,170 Serbs remained, the majority of whom were elderly. By the time of the official 2021 census, that number had declined to fewer than 1,000 individuals.
Belgrade/Banja Luka, October 30, 2026
Information Service of the DIC “Veritas”
