UN in new South Sudan peace plea as reinforcements loom
The BBC's Anne Soy reports on the evacuation of Kenyan nationals from South Sudan: ''A long, difficult, uncertain journey''
The UN has renewed its call for rival forces in South Sudan to lay down their arms and says it expects the first UN reinforcements to arrive in 48 hours.
The plea came as South Sudan's President Salva Kiir met the leaders of neighbouring Kenya and Ethiopia in an effort to defuse the conflict.
Government officials say a number of oil wells are now in rebel hands.
Violence erupted 11 days ago between forces loyal to the president and those backing his ex-deputy Riek Machar.
UN special representative Hilde Johnson urgently called on the country's political leaders "to give peace a chance".
"The nation that [was] painstakingly built over decades of conflict and strife is at stake," she said, speaking via a video link from South Sudan's capital, Juba.
Ms Johnson said "well over 1,000" people had been killed since the start of the violence on 15 December and the casualty figures were likely to rise.
She said she expected some UN military reinforcements and critically needed equipment within 48 hours.
'Lawless'Ms Johnson said there had been heavy fighting in Malakal and Bor, while the town of Bentiu had become calmer.
The leaders of Ethiopia, South Sudan and Kenya met in Juba on Thursday 
The UN says tens of thousands of civilians have had to flee their homes as the fighting spread 
The situation in the town of Bor is said to be calmer after government troops recaptured it The Bishop of Malakal, Hilary Garang, said the situation in the main town in Upper Nile state was one of lawlessness.
"There is no government functioning, there is no light, there is no water and people are fleeing, are going away. The town is divided in two," he told the BBC's Newshour programme.
"The two sides are taking positions and fighting can erupt any time they choose.
"Today there is heavy shelling. About five shells fell in the middle of the town in part of the market and also on some houses and even close to my residence where I am, near the church," Bishop Garang said.
The fighting is also affecting oil production, which accounts for 98% of government revenue.
"Some oil wells are in the hands of rebel soldiers loyal to... Machar and we fear they may cause damage to the facilities and the environment," Petroleum Minister Stephen Dhieu Dau told Reuters news agency.
He said the Thar Jath oil field in Unity state had been captured by the rebels.
'Political conflict'Ms Johnson said there had been internal tension within the governing Sudan People's Liberation Movement (SPLM) before the outbreak of violence.
Ethiopia's Foreign Minister Tedros Adhanom: ''Any solution to this crisis should be through political dialogue''
But, she said, no-one had expected "the unravelling of [South Sudan's] stability so quickly".
Ms Johnson said the speed, gravity and scale of the violence had caught everyone by surprise.
She insisted that while the rival leaders came from different ethnic groups - Mr Kiir is a Dinka and Mr Machar is from the Nuer tribe - the conflict was political.
She said the United Nations was working around the clock to get reinforcements into the country.
On Tuesday, the UN Security Council decided to boost the existing UN force (Unmiss) of around 7,000 peacekeepers and police to about 14,000.
Coup allegationsThe violence first erupted after a meeting of the SPLM's high council on 15 December.
President Kiir accused the former vice-president, who had been sacked in July, of plotting a coup.
Mr Machar denied any involvement and said the accusations were an attempt by Mr Kiir to get rid of his political rivals.
The fighting quickly spread to half of Sudan's 10 states.
On Thursday, President Kiir held talks with Ethiopian PM Hailemariam Desalegn and Kenyan President Uhuru Kenyatta, currently head of the East African Community, in an effort to find a negotiated solution to the conflict.
However, South Sudan Information Minister Makuei Lueth told Associated Press no contact with Mr Machar had yet been established.
South Sudan has struggled to achieve a stable government since becoming independent from Sudan in 2011.
Fighting erupted in the South Sudan capital, Juba, in mid-December. It followed a power struggle between President Salva Kiir, a Dinka, and his Nuer ex-deputy Riek Machar. The fear is that the rivalry will spark a widespread ethnic conflict. According to OCHA, 81,000 people have been forced from their homes. 
Sudan's arid north is mainly home to Arabic-speaking Muslims. But in South Sudan there is no dominant culture. The Dinkas and the Nuers are the largest of more than 200 ethnic groups, each with its own languages and traditional beliefs, alongside Christianity and Islam. 
Both Sudan and the South are reliant on oil revenue, which accounts for 98% of South Sudan's budget. They have fiercely disagreed over how to divide the oil wealth of the former united state - at one time production was shutdown for more than a year. Some 75% of the oil lies in the South but all the pipelines run north 
The two Sudans are very different geographically. The great divide is visible even from space, as this Nasa satellite image shows. The northern states are a blanket of desert, broken only by the fertile Nile corridor. South Sudan is covered by green swathes of grassland, swamps and tropical forest. 
After gaining independence in 2011, South Sudan is the world's newest country - and one of its poorest. Figures from 2010 show some 69% of households now have access to clean water - up from 48% in 2006. However, just 2% of households have water on the premises. 
Just 29% of children attend primary school in South Sudan - however this is also an improvement on the 16% recorded in 2006. About 32% of primary-age boys attend, while just 25% of girls do. Overall, 64% of children who begin primary school reach the last grade. 
Almost 28% of children under the age of five in South Sudan are moderately or severely underweight - this compares with the 33% recorded in 2006. Unity state has the highest proportion of children suffering malnourishment (46%), while Central Equatoria has the lowest (17%). 
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