At least 30 people were killed when militia opposed to the Southern Sudanese government launched a failed overnight raid on a strategic town on Saturday, said army and U.N. officials.
Fighting between Sudan People's Liberation Army forces and a militia led by a man known as Capt. Olonyi started outside the capital of the oil-rich border state of Upper Nile in the early hours of Saturday morning, said U.N. spokeswoman Hua Jiang. Olonyi is a little-known militia leader from a discontented minority ethnic group.
Jiang said the southern army repelled the attack on the city of Malakal.
At least 30 rebels were killed and four government soldiers were killed, said army spokesman Col. Philip Aguer. He did not have figures for civilian casualties.
"Twenty-one people have been admitted so far to the hospital, including three young children," said Bartholomew Pakwan Abwol, a spokesman for the Upper Nile state government.
Abwol said many of those admitted had suffered bullet wounds.
"The (army) is in control of Malakal," he said. "They didn't attack the SPLA headquarters, they were attacking the center of town."
Last Sunday, 62 people were killed and 71 wounded in fighting between Olonyi's forces and the southern army in a village north of Malakal, according to an internal U.N. security report released after the attack and viewed by The Associated Press.
Aguer said Olonyi's forces are supporters of an opposition party which broke away from the south's ruling party in 2009. The leader of that party, Lam Akol, is viewed by some southern leaders as an operative for the northern Sudanese government. The oil-rich south is due to secede from the north in July following a referendum held after decades of civil war. Akol has denied any links to the militia or to other armed rebel forces in the south.
Olonyi has not made any recent public statement about the motives behind his group's recent violence. An un-implemented cease-fire between other armed members of his Shilluk ethnic group and the army and an unresolved land dispute between his ethnic group and another community may be among the reasons for the attacks.
The ongoing violence in the period between the south's peaceful referendum in January and its declaration of independence on July 9 shows dangerous internal divides exist that could destabilize the south after it becomes the world's newest nation.
Claire McEvoy of the Geneva-based Small Arms Survey, which studies conflict in Sudan, warned rebels like Olonyi "have the potential to become magnets for other dissatisfied southerners" who oppose the south's ruling party.
"Associated violence has the potential to escalate as more southerners are affected by related killings and displacement," McEvoy added, noting that the southern government is unable to provide security and basic services for its people.
Southern authorities have often accused the northern Sudanese government of stoking violence in the south.
On Saturday, top southern officials visiting the northern capital repeated accusations that the north is working to destabilize the south, and said the southern government was considering halting the movement of oil from the south to the north.
Pagan Amum, who heads the Southern Peoples' Liberation Movement, the political arm of Southern Sudan's ruling party, charged that north Sudan's National Congress Party has trained and dispatched destabilizing elements to the border area between the north and the south.
"The militias and the armed groups that attack the government of southern Sudan receive support from the national congress and are under the command of the National Congress Party," he said. ".... we have been instructed to study the possibly of halting pumping petroleum via northern Sudan and to come up with alternatives after the 9th of July."
McEvoy said the hidden hand of northern involvement should not be discounted.
"There is also a long history of dissenters in the South being backed by military intelligence in the north as a means of destabilizing it, and the potential for this remains," she said.
Associated Press writer Mohamed Osman contributed to this report from Khartoum, Sudan.