JUBA, South Sudan (AP) -- Rebel forces took control of parts of the capital of South Sudan's oil-producing Upper Nile state, a military official said Tuesday, as the United Nations said at least 10 people died following the latest outbreak of violence in the world's newest country.
Fighting broke out early Tuesday in Malakal, which once was in rebel hands but is now mostly controlled by government troops, said South Sudanese military spokesman Col. Philip Aguer.
Aguer said the rebels now control parts of eastern Malakal and suggested they had received reinforcements from outside the country.
"Possible external support to the rebels is there," Aguer said. "There is lot of evidence that planes have been landing, planes dropping ammunition, whose planes we don't know. Where they came from we don't know. That is the subject of an investigation."
The same allegation was made by presidential spokesman Ateny Wek Ateny, who said the rebels have the backing of "certain international actors."
Neither official said who they believe is giving support to rebel forces.
The international community --including the U.S. and the U.N.-- have repeatedly urged both sides to respect the cease-fire and to start serious talks aimed at finding a political solution.
At least 10 people died at a U.N. hospital in Malakal from injuries sustained during "inter-communal violence" within the U.N. compound as well as clashes outside it, said the U.N. mission in South Sudan in a statement Tuesday. It said there was a threat to the U.N. compound in Malakal, forcing U.N. troops to "concentrate on protecting the perimeter of the camp from this external threat."
Armed groups had gathered outside the U.N. compound in Malakal, where more than 21,000 people are sheltering, said Grace Cahill, a spokeswoman for Oxfam in South Sudan.
Both sides have repeatedly accused each other of violating the cease-fire even as peace talks proceed slowly.
Lul Koang, a Kenya-based brigadier who speaks for rebel forces, said fighting Tuesday was sparked by "unprovoked" attacks on rebel positions south and east of Malakal. He said South Sudanese ground forces received "massive air support from Ugandan warplanes" in the latest fighting. Aguer, the South Sudanese military spokesman, denied Ugandans were fighting in Malakal.
The U.N. says both sides have committed rights violations, and on Monday South Sudan's military announced more than 20 government soldiers had been charged over civilian killings.
Thousands of people have been killed and more than 800,000 displaced by violence since mid-December, when a fight broke out among presidential guards in the capital, Juba, before spreading out across the country. Ugandan forces are fighting alongside the South Sudanese military as it tries to put down a rebellion led by former Vice President Riek Machar, an influential politician whose dismissal last year sparked ethnic tension in a country with a history of divided military loyalties.
The U.S. has urged all foreign militaries fighting in South Sudan to withdraw from the country, and the rebels have said the presence of Ugandan troops in South Sudan is an obstacle to achieving a peace deal.
Ugandan Foreign Minister Sam Kutesa said Tuesday that Uganda will not withdraw its troops that are backing South Sudan's government until the African Union deploys a planned "standby force" in the country. The African Union says such a force would have the capacity to respond rapidly to outbreaks of violence across the continent, but it may take months -- even years-- to realize this plan.
Most of the loyalist forces are from the Dinka ethnic group of President Salva Kiir, whose government insists that unrest in the country was sparked by a failed military coup mounted by soldiers loyal to Machar. Machar is Nuer, the ethnic group of most of the soldiers who defected and joined his rebellion late last year. Machar denies the coup allegation but says his goal is to have Kiir removed from power.
Associated Press reporters Rodney Muhumuza in Kampala, Uganda, and Elias Meseret in Addis Ababa, Ethiopia, contributed to this report.
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