Tens of thousands of Bosnian Muslims gathered for a ceremony on Sunday, to commemorate the exact day fifteen years ago when the town of Srebrenica was overrun by Serb Forces. More than 8000 men and boys were killed in the two days that followed, as United Nations forces simply stood by. This the darkest episode of the Bosnian war continues to haunt relations between Bosnia's Serb and Muslim Croat populations.