Thousands of people have been fleeing the South Sudanese town of Akobo and surrounding parts of Jonglei state, where the army says it has intensified strikes on its enemies to regain control. The latest fighting has led the UN to warn of a possible return to full-blown civil war in the world's youngest nation. Nyawan Koang, 30, and her five children had to walk for two days to reach the dusty village of Duk. They had fled Ayod, a remote and largely pastoralist county in Jonglei state, where armed clashes had been raging between the military and their opponents who had been fortifying their presence there since the beginning of the year. "We were [wedged] between two forces: the SPLA-IO and the government. And their bullets kill us," she told the BBC. Government forces are trying to retake territory from those loyal to First Vice-President Riek Machar, who has been suspended from his post after being accused of plotting to overthrow President Salva Kiir.…