As the conflict in South Sudan gains in intensity, world leaders have urged the feuding parties to find a political resolution to the crisis. Observers fear ethnic tensions in the country could lead to a civil war.
United Nations Secretary-General Ban Ki-moon has joined the growing chorus of voices calling for peace in South Sudan, where the death toll is mounting amid fighting between forces loyal to the president and followers of his sacked deputy.
"I demand that all political, military and militia leaders stop hostilities and end the violence against the civilians," Ban told a news briefing on Sunday during a visit to the Philippines.
He called on South Sudanese President Salva Kiir and his rival, former vice president Riek Machar, to "find a political way out of this crisis."
Earlier, United States President Barack Obama issued a statement after four US service members were wounded in an attack on three US aircraft on a mission to evacuate American citizens in the rebel-held flashpoint town of Bor.
Obama warned against a coup attempt, saying: "Any effort to seize power through the use of military force will result in the end of longstanding support from the United States and the international community."
He also called on South Sudanese leaders to help protect American citizens and personnel both in the capital, Juba, and in Bor, where a number of civilians have reportedly been killed in fighting.
It remains unclear who fired on the aircraft.
Britain, Kenya and Uganda have also been evacuating their nationals as the situation in South Sudan becomes more dangerous, as has also been underlined by an attack on a UN base in recent days that ended in the deaths of two Indian peacekeepers and possibly dozens of civilians.
President Kiir maintains that the violence in the country was triggered by an attempted coup mounted by his former deputy Machar, while Machar denies this and claims Kiir is carrying out a violent purge. The conflict also has an ethnic dimension, with Kiir being an ethnic Dinka, while Machar belongs to the Nuer tribe.
A week of fighting has seen at least 500 people killed in Juba alone, and tens of thousands of South Sudanese have fled their homes.
South Sudan is the world's newest nation, having split from its northern neighbor, Sudan, in 2011 after a two-decade civil war that claimed two million lives.
tj/msh (AFP, AP)