South Sudan: UN condemns refugee camp air raid
The UN has denounced the bombing of a camp housing some 5,000 refugees in South Sudan near the border with Sudan.
A boy was injured and 14 other people went missing during the air raid in El Foj in Upper Nile state on Monday, the UN refugee agency said.
A Sudan army spokesman told the BBC that Sudanese forces had not carried out any bombing raids in the area.
South Sudan split from Sudan last July and since then their relationship has deteriorated.
Both countries accuse the other of backing rebels operating in their territories and it is not the first time South Sudan has been bombed - there were attacks in Upper Nile state and Unity state last year.
The UNHCR says a plane dropped several bombs on Monday morning which landed on the transit site for those who have fled the conflict in Blue Nile over the border in Sudan.
"Bombing of civilian areas must be condemned in the strongest terms," Mireille Girard, UNHCR's representative in South Sudan, said in a statement.
The BBC's James Copnall in Sudan's capital, Khartoum, says the UN did not say who was responsible, but the refugees will almost certainly suspect the Sudanese Armed Forces.
Blue Nile is one of three border areas - along with South Kordofan and Abyei - where fighting has broken out since South Sudan's independence.
Many rebels in these regions fought alongside southerners during the decades-long civil war that ended with Khartoum agreeing to the south's independence.
Sudan's army spokesman Khalid Sawarmi said Sudanese forces had been recently involved in fighting against rebels in Blue Nile in the village of Aroum.
"We attacked them and drove them out of this place. [We] did not use any planes or Antonovs there," he told the BBC.
Following the strike on El Foj, most people have now fled the area or have been helped to relocate by the UN, the agency says.
The authorities in Upper Nile state say they do not have first-hand confirmation of an incident at El Foj.
However Upper Nile's Information Minister Peter Lam Both did accuse Sudan of carrying out another air raid in the state on Sunday.
He told the BBC that three people were killed and four wounded in Khor Yabous, near the border with Sudan.
He also said South Sudan's army had fought off an attack by militias around this time.
The UN says more than 78,000 people have fled Sudan since last August because of fighting in Southern Kordofan and Blue Nile.
Our correspondent says the latest incident highlights the bad relationship between the two countries as well as the difficult situation many refugees face.
Recently the focus has been on oil resources, with South Sudan deciding last week to shut down its production rather than, as it sees it, have some of its oil stolen by the north, he says.
The two sides are currently discussing how to share their oil resources at talks in Ethiopia.
But whatever the full truth of the matter, the greatest concern to many is security not oil, our reporter says.
Both Sudan and the South are reliant on their oil revenues, which account for 98% of South Sudan's budget. But the two countries cannot agree how to divide the oil wealth of the former united state. Some 75% of the oil lies in the South but all the pipelines run north. It is feared that disputes over oil could lead the two neighbours to return to war.
Although they were united for many years, the two Sudans were always very different. 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.
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.
The health inequalities in Sudan are illustrated by infant mortality rates. In South Sudan, one in 10 children die before their first birthday. Whereas in the more developed northern states, such as Gezira and White Nile, half of those children would be expected to survive.
The gulf in water resources between north and south is stark. In Khartoum, River Nile, and Gezira states, two-thirds of people have access to piped drinking water and pit latrines. In the south, boreholes and unprotected wells are the main drinking sources. More than 80% of southerners have no toilet facilities whatsoever.
Throughout the two Sudans, access to primary school education is strongly linked to household earnings. In the poorest parts of the south, less than 1% of children finish primary school. Whereas in the wealthier north, up to 50% of children complete primary level education.
Conflict and poverty are the main causes of food insecurity in both countries. In Sudan, many of the residents of war-affected Darfur and the border states of Blue Nile and South Kordofan, depend on food aid. The UN said about 2.8m people in South Sudan would require food aid in 2013. The northern states tend to be wealthier, more urbanised and less reliant on agriculture.