NAIROBI, Kenya (AP) -- Unknown gunmen fired guns and rocket-propelled grenades at a convoy of barges on the Nile River in South Sudan that were being used by the U.N. to deliver food and fuel, the U.N. mission said. Four people, including peacekeepers, on board were wounded.
The attack Thursday took place as the barges were traveling to the city of Malakal. South Sudan has a poor road network and barges are frequently to transport goods.
The U.N. mission said it was unable to identify the assailants and that military and rebel leaders both denied responsibility. The U.N. mission said the injuries to the four barge crew members and peacekeepers were not considered to be life-threatening. It didn't provide a breakdown of how many peacekeepers were hurt.
South Sudan has been rocked by violence since December, when the president accused the former vice president of staging a coup.
The U.N. Security Council on Thursday expressed "horror" at the recent massacre of several hundred civilians in the city of Bentiu by rebel fighters. It said council members may be willing to impose sanctions if attacks on civilians continue.
The condemnations come about 10 days after rebel fighters from the Nuer ethnic group took control of Bentiu and slaughtered non-Nuer civilians in the town mosque, the hospital and on streets, leaving "piles and piles" of bodies, according to the U.N.'s top aid official in the country.
South Sudan became the world's newest country in 2011 when it cleaved off from larger Sudan after a referendum. Enmities between ethnic groups have been longstanding.
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