UN Secretary General Ban Ki-moon came in for tough criticism Thursday from Sri Lanka's government, which accused him of unwittingly helping Tamil Tiger rebels. Responding to the UN chief's concern over civilians displaced by heavy fighting in the north of the island, a Sri Lankan government rights official said a government offensive had caused hardly any civilian casualties. Ban had on Tuesday reminded the Sri Lankan government and the Liberation Tigers of Tamil Eelam (LTTE) of their obligations to ensure the safety of civilians.