EDWARD McCALLISTER THE United Nations has called for an investigation after Reuters reported that Cameroonian soldiers opened fire on fleeing civilians during a weekend raid, killing up to nine people. Three witnesses told Reuters that soldiers entered the village of Mautu in the South West region - at the heart of a separatist insurgency - raided homes and shot civilians as they ran for cover under nearby cocoa bushes. The Cameroonian military denies wrongdoing. It said it was conducting a raid on separatist positions when it came under fire and had killed what it labelled "terrorists". "Deeply concerned & saddened…