Dozens dead as south Sudan army and rebels clash again
Dozens of people have died in clashes between Southern Sudan's army and George Athor's rebels, officials say.
The fighting began on Sunday in Fangak county, the same area where more than 200 people were killed last month.
Mr Athor defected from the army last year, alleging fraud in state elections, though his group signed a ceasefire agreement in January.
The violence has raised concerns about the stability of a state born only last month in an independence referendum.
George Athor claims 110 people were killed in the latest round of fighting, most of them army soldiers.
The southern army spokesman Col Philip Aguer said Mr Athor's death toll was exaggerated, and that the deaths were something to mourn, not something to be proud of.
Col Aguer estimated the number killed at around 40, although he said details were still sketchy.
Our correspondent in the southern capital, Juba, Peter Martell, says the battles are localised and are very unlikely to affect the rest of the south, but it is one more sign of the challenges the south faces to improve security and bring its people together.
Mr Athor told Reuters news agency he was ready to return to negotiations with the southern leadership.
"I am really worried because the new country will be like a baby born dead," he was quoted as saying. "If you start with a guerrilla force fighting the government, I don't see any development that can happen."
Col Aguer reportedly said the rebel leader was "refusing peace, amnesty, and the cease-fire".
Mr Athor was a senior member of the Sudan People's Liberation Army during the war against the north. He turned renegade last April, claiming he was cheated out of victory in elections for the post of state governor of Jonglei.
Despite a ceasefire agreement in January, clashes broke out in Jonglei in February. The Southern Sudanese government said some 200 people were killed, most of them civilians, in what they called a "massacre" by Mr Athor's forces.
Southern officials have accused the rebel leader of taking arms from former civil war enemies in the north, something that Khartoum has denied.
Our correspondent says analysts doubt that Mr Athor would ally himself with the north and think it more likely that he began his rebellion after falling out with senior leaders in the southern government.
Southern Sudan is set to become the world's newest independent state on 9 July.
Leaders from north and south are holding talks in Ethiopia this week on future economic and political relations between the two countries.
Both Sudan and the South are reliant on their oil revenues, which account for 98% of South Sudan's budget. But the two countries cannot agree how to divide the oil wealth of the former united state. Some 75% of the oil lies in the South but all the pipelines run north. It is feared that disputes over oil could lead the two neighbours to return to war.
Although they were united for many years, the two Sudans were always very different. The great divide is visible even from space, as this Nasa satellite image shows. The northern states are a blanket of desert, broken only by the fertile Nile corridor. South Sudan is covered by green swathes of grassland, swamps and tropical forest.
Sudan's arid north is mainly home to Arabic-speaking Muslims. But in South Sudan there is no dominant culture. The Dinkas and the Nuers are the largest of more than 200 ethnic groups, each with its own languages and traditional beliefs, alongside Christianity and Islam.
The health inequalities in Sudan are illustrated by infant mortality rates. In South Sudan, one in 10 children die before their first birthday. Whereas in the more developed northern states, such as Gezira and White Nile, half of those children would be expected to survive.
The gulf in water resources between north and south is stark. In Khartoum, River Nile, and Gezira states, two-thirds of people have access to piped drinking water and pit latrines. In the south, boreholes and unprotected wells are the main drinking sources. More than 80% of southerners have no toilet facilities whatsoever.
Throughout the two Sudans, access to primary school education is strongly linked to household earnings. In the poorest parts of the south, less than 1% of children finish primary school. Whereas in the wealthier north, up to 50% of children complete primary level education.
Conflict and poverty are the main causes of food insecurity in both countries. In Sudan, many of the residents of war-affected Darfur and the border states of Blue Nile and South Kordofan, depend on food aid. The UN said about 2.8m people in South Sudan would require food aid in 2013. The northern states tend to be wealthier, more urbanised and less reliant on agriculture.