Juba - South Sudan accused Sudan of launching air strikes on the southern side of their disputed border shortly before the leaders of the oil-producing African countries were due to meet to defuse tensions.
Several civilians were wounded in the attack in the southern state of Western Bahr El Ghazal on Wednesday, South Sudan's Information Minister Barnaba Marial Benjamin told journalists.
Sudan's armed forces were not immediately available for comment but have regularly denied southern accusations of attacks in the past.
The two countries have been at loggerheads over oil, territory and a string of other disputes since the South split away from Sudan last year under the terms of a peace deal.
They came close to war in April and have yet to withdraw their armies from their shared boundary or resume oil exports from the landlocked South north through Sudanese pipelines.
Sudan President Omar Hassan al-Bashir and his South Sudan counterpart Salva Kiir were due meet at a summit in Ethiopia on Friday to discuss how to set up the demilitarised border zone they agreed upon at a meeting in September.
Both presidents said this week they wanted to implement the September deals but diplomats are sceptical about the chances of a quick breakthrough.
“There were attacks yesterday (Wednesday) ... in the area of Kit Kit ... There was both ground and aerial bombardment,” South Sudan's Barnaba Marial Benjamin told journalists in the South's capital Juba.
“The South Sudan armed forces were able to repulse the attack but the aerial bombardment has caused a lot of injuries to the civilians in the area,” he said.
Sudan's army spokesman al-Sawarmi Khalid could not be reached on his mobile phone.
Sudan regularly denies launching air strikes against the South though Reuters reporters witnessed several attacks when border fighting escalated in April. The ownership of many areas close to the border is disputed by both countries.
South Sudan, which inherited three-quarters of oil production when it broke away, shut down its entire output of 350,000 barrels a day in January after tensions over pipeline fees escalated.
Both sides have a history of first signing and then not implementing agreements due to a deep mistrust going back to the north-south civil war, fuelled by oil, ethnicity and ideology that led up to last year's partition.
Sudan accuses South Sudan of supporting rebels who operate in two states on the border with South Sudan. Juba has denied the charge and accuses Khartoum of backing rebels on its territory.
Both countries need the oil to support their crumbling economies. Analysts say both governments are also using the confrontation to shore up domestic support and divert attention from a lack of development. - Reuters