Ustaše were making lists of Serbs which they used for deportations to Serbia. About 175,000 Serbs were deported from NDH to Serbia during the first two years of NDH's existence. The regime systematically and brutally massacred Serbs in villages in the countryside, using a variety of tools. In addition, Nazi-style concentration camps were set up for enemies of the state, the most notorious being Jasenovac where some 50,000 Serbs were killed. Sisak and Jastrebarsko concentration camp were specially formed for children. During the war, around 300,000 Serbs are estimated to have been murdered under the Ustashe regime as a result of their genocide campaign. Diana Budisavljević, a humanitarian of Austrian descent, carried out rescue operations and saved more than 15,000 children from Ustashe camps. Budisavljević and her team was assisted by the Croatian Red Cross and the Zagreb Archdiocese branch of Caritas. Thousands of rescued Serb children were placed with ethnic Croat families from Zagreb and rural communities. The Ustasha policy towards Serbs further drove a number of them joined either Chetniks or the Yugoslav Partisans who were particularly strong in the regions of Lika, Kordun and Banovina. In 1941–42, the majority of Partisans in Croatia were Serbs, but by October 1943 the majority were Croats. This change was partly due to the decision of a key Croatian Peasant Party member, Božidar Magovac, to join the Partisans in June 1943, and partly due to the surrender of Italy in September 1943. Furthermore, Ustashe authorities ceding Northern Dalmatia to fascist Italy, Italian terror of the population and misrule of the Ustashe and Axis invaders would further push Croats towards the partisans. At the moment of the capitulation of Italy to the Allies the Serbs and Croats were participating equally according to their respective population sizes as it was in Yugoslavia as a whole. Eventually, Serbian percentage dropped in favor of Croats by the end of the war amounting to 28.6% in 1944 in Croatia. The Serb contribution to Croatian Partisans represented more than their proportion of the local population. After the invasion of Yugoslavia by Axis forces, Serbian uprisings broke out under the Chetnik leadership in Gračac, Srb, Donji Lapac, Drvar and Bosansko Grahovo. The policy of the Chetniks under the leadership of Draža Mihailović varied from the struggle with the Nazis to tactical or selective collaboration with them in different periods throughout the war. The goal of the Chetniks, based