The United Nations is warning of possible “mass atrocity crimes” in Burma amid reports that tens of thousands of troops are massing into relatively restive regions in the north and northwest. The U.N. special rapporteur for the region said the military government likely engaged in crimes against humanity and war crimes. According to a local monitoring group, nearly 1,200 civilians have been killed and over 7,000 arrested since protests erupted following February’s military coup.