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.