JUBA, South Sudan — Fresh fighting broke out between rival soldiers in South Sudan, threatening a fragile peace agreement forged with the help of outsiders including the United States.
Sporadic fighting was reported Thursday in Upper Nile state, according to spokesmen for the rival groups.
Army Maj. Gen. Lul Ruai Koang, spokesman for South Sudanese government troops, charged that rival forces — known officially as the Sudan People’s…

