Fighting escalated in South Sudan yesterday, with a top commander in the country's key oil-producing region defecting to the rebels and foreign governments scrambling to evacuate their nationals.
A US military aircraft was shot at as it was engaged in evacuation operations in Bor, the rebel-held capital of Jonglei state, a diplomatic source and Ugandan military officials said, with some US military personnel injured in the incident.
The upsurge in hostilities in the world's youngest nation came despite an offer from President Salva Kiir to open talks with his former deputy Riek Machar, who is accused of having started the fighting by attempting a coup.
Machar in turn accuses Kiir of conducting a violent purge, and has quickly built up a rebel army to take on the central government on several fronts.
At least 500 people have been killed in Juba alone in six days of fighting, while tens of thousands have been displaced -- many of them seeking shelter in UN bases across the country amid warnings that the impoverished nation is on the brink of all-out civil war.
US President Barack Obama has warned that hopes for South Sudan at its independence from Sudan in July 2011 are now "at risk", amid reports from rights groups of an upsurge in ethnic killings. US Secretary of State John Kerry said Friday he was sending Donald Booth, his special envoy for Sudan and South Sudan, to the region to encourage talks between the warring factions.
Neighbouring Kenya yesterday ordered troops into the country to evacuate Kenyans stranded there, following Uganda, which has already sent in a special forces unit to help evacuate its nationals.
Juba's main bus park was crowded with people struggling to find space on public transport, while foreigners have headed to the airport where several countries -- including the United States and Britain -- have sent military transport planes to evacuate their nationals.
South Sudan gained independence from Sudan as part of a peace process after a two-decade civil war that left two million dead, but it has never been able to heal its own ethnic rivalries.