At least 140 people have been killed in ethnic clashes in southern Sudan. Deputy governor of Warrap state Sabino Makana said members of the Nuer group attacked Dinka cattle herders killing 139 of them and wounding dozens more. They also seized thousands of animals. He said most of the violence happened over the weekend in Tonj village. Senior UN official Lise Grande confirmed the clashes. <br/><br/>According to local sources on the ground, at least 140 people had been killed, 90 wounded and 30,000 head of cattle had been stolen. The UN said more than 2,000 people have been killed in ethnic violence in the south since last January. <br/><br/>Meanwhile, ten international aid agencies have warned that Sudan is on the verge of collapse and it faces a return to war.