Fighting in South Sudan has spread to areas beyond the country's capital, where clashes began Sunday in what the government called an attempted coup.
The U.N. mission in South Sudan reported heavy fighting in the city of Bor early Wednesday that lasted for about four hours before decreasing in intensity. The mission said more than 1,000 civilians have sought shelter at its compound in Bor, which is about 150 kilometers north of Juba. There was also fighting overnight at a military base in Torit, southeast of the capital.
U.N. peacekeeping chief Herve Ladsous reported Tuesday to the Security Council that local hospitals said at least 400 people have been killed in Juba, but that the U.N. had not been able to verify the toll.
In a statement late Tuesday, the council expressed concern about the risk of violence targeting certain groups and called for South Sudan's government to hold talks with its opponents.
U.S. Secretary of State John Kerry said Wednesday that the people of South Sudan have sacrificed too much for their country to return to violence.
"Political differences need to be resolved by peaceful and democratic means and those have been hard fought for. The government should respect the rule of law and the people of South Sudan should be able to realize their full potential in peace."
President Salva Kiir blamed the coup attempt on forces loyal to his former vice president, Riek Machar, whom he fired in July.
Observers have raised concerns that a rift between Machar, from the Nuer ethnic group, and Mr. Kiir, a Dinka, could fuel tribal violence in South Sudan.
South Sudan's government said 10 people have been arrested for their alleged roles in the coup attempt, while Machar remains at large. The government also said it expected to reopen Juba's airport to both domestic and international flights on Wednesday.
Government security forces have imposed a nighttime curfew in Juba and were searching door-to-door for those blamed for the fighting.
The president of the U.N. Security Council, French Ambassador Gerard Araud, said as many as 20,000 people have taken refuge with the U.N. mission in Juba.
The U.S. State Department has ordered the departure of all non-essential personnel from South Sudan and is urging all Americans in the country to leave immediately.