Wikipedia
The Schutzkorps ("Protection Corps") was an auxiliary volunteer militia established by Austro-Hungarian authorities in the newly annexed province of Bosnia and Herzegovina to track down Bosnian Serb opposition (members of the Chetniks and the Komiti). It was predominantly recruited among the Bosniak population and was known for its part in the persecution of Serbs. They particularly targeted Serb populated areas of eastern Bosnia.
The role of Schutzkorps is a point of debate. Persecution of Serbs conducted by the Austro-Hungarian authorities was the first large-scale persecution of people because of their ethnicity and first incidence of active "ethnic cleansing" in Bosnia and Herzegovina, but Serb casualties in Eastern Bosnia were partially the result of activities undertaken in retaliation to Serbian Chetniks who in fall 1914 had carried out attacks against Bosniaks in the area. Some Bosniak leaders emphasized that it would be wrong to blame the whole Bosniak population of Bosnia and Herzegovina for misdeeds of Schutzkorps, because some Bosniaks provided help to their Serb neighbors, while some Serbs hid from persecution by applying into Schutzkorps.