At least 140 people have been killed and 90 wounded in the remote troubled Wunchuei region of Warrap state in southern Sudan over the past week, a senior UN official said on Thursday. Clashes, apparently between rival tribal groups, occurred some time since the beginning of the year but reports emerged only after a UN security team visited the remote area by aircraft two days ago. "Local sources on the ground said that at least 140 people had been killed, 90 wounded and 30,000 head of cattle had been stolen," said Lise Grande, the UN Deputy Resident and Humanitarian Coordinator in south Sudan.