 In the following months, many Serbs from Mostar and the surrounding area were transported to Ustasha concentration camps, mainly Jasenovac, while many others fled to Nazi-occupied Serbia.Around 8,000 Serbs lived in Mostar before the massacres started on 24 June 1941, and by the end of August only around 850 remained.The Serb singing society "Gusle" was founded on December 18, 1888 in Mostar.