Nearly 340,000 Rohingya children are seeing a "hell on earth" by living in squalid conditions in Bangladesh camps where they lack enough food, clean water and health care, the United Nations Childrens Fund (UNICEF) said on Friday. Up to 12,000 more children join them every week, fleeing violence or hunger in Myanmar, often still traumatised by atrocities they witnessed, UNICEF said in a report "Outcast and Desperate.” In all, almost 600,000 Rohingya refugees have left northern Rakhine state since Aug. 25 when the UN says the Myanmar army began a campaign of "ethnic cleansing.” "This isnt going to be a short-term, it isnt going to end anytime soon," Simon Ingram, the reports author and a UNICEF official, told a news briefing in Geneva. "These children just feel so abandoned, so completely remote, and without a means of finding support or help. In a sense, its no surprise that they must truly see this place as a hell on earth," Ingram said. The report comes ahead of a donor conference Monday in Geneva to drum up funding for the Rohingya. The UN and humanitarian agencies seek $434 million for the Rohingya refugees — about one-sixth of which would go to UNICEF efforts to help children. "Many Rohingya refugee children in Bangladesh have witnessed atrocities in Myanmar no child should ever see, and all have suffered tremendous loss," UNICEF Executive Director Anthony Lake said in a statement. UN agencies are still demanding access to northern Rakhine, where an unknown number of Rohingya remain despite UN reports that many villages and food stocks have been burned. "We repeat the call for the need for protection of all children in Rakhine state, this is an absolute fundamental requirement. The atrocities against children and civilians must end," Ingram said. "We just must keep putting it on the record, we cannot keep silent," he added.