Refugees caught in mud flows , runoff from flooded latrines , internal U.N. memo says . More than 300 families protest conditions , memo says . Score: 6 Human Rights Watch has called for immediate release of Tamil civilians at camps .
Refugees caught in mud flows , runoff from flooded latrines , internal U.N. memo says . More than 300 families protest conditions , memo says . Flooding comes ahead of Sri Lanka 's monsoon season . Human Rights Watch has called for immediate release of Tamil civilians at camps .