Government forces in South Sudan have retaken the strategic town of Nasir in Upper Nile state attacked by rebels on Sunday, the UN says. It was the scene of the worst clashes since a ceasefire was agreed in May. UN peacekeepers say there was heavy gunfire in the town overnight and early in the morning. Further talks are due to start next week as attempts continue to end the conflict that broke out in December, leaving 1.5 million people homeless. What began as a political dispute between President Salva Kiir and his...