NDH authorities took communists, Jews, Serbs and those suspected of being members of the resistance movement or working against the Ustasha regime as hostages and often shot them in retaliation for riots or attacks on NDH individuals or institutions. Towards the end of the war, random citizens of Zagreb were also taken away. Hostages were shot in the forest along the Dortščina stream in the east of the city and the Stupnički lug forest in Rakov Potok, on the south.
Information about shootings with the names of those killed was published on posters, which could be seen everywhere in the city. In this way, the Ustashas wanted to intimidate other citizens and spread fear in society, as well as prevent resistance and rebellions against the imposed system of terror.