Four foreigners investigating debris from recent fighting between Sudan and South Sudan have been caught in the Heglig oilfield area, Khartoum said Saturday, but the UN identified them as deminers. "This confirms what we said before, that South Sudan in its aggression against Heglig was supported by foreign experts," army spokesman Sawarmi Khaled Saad told reporters after the four were flown to Khartoum for "more investigation." He identified the captives as a Briton, a Norwegian, a South African and a South Sudanese. "We captured them inside Sudan's borders, in the Heglig area, and they were collecting war debris for investigation," Saad said at the airport. Jan Ledang, country director for the Norwegian People's Aid (NPA) mission in South Sudan, identified one of the captives as John Sorbo, also of NPA. "It's impossible that they were in Heglig -- they were in Pariang" about a 90-minute drive from Heglig in the South's Unity state, Ledang said. They were doing some follow-up demining work in that area, he added. Josephine Guerrero, a spokesperson for the United Nations Mission in South Sudan, said the four were on a de-mining mission "and one of them was from the UN." In the most serious unrest since the South's independence, Juba's troops occupied Sudan's main oil region of Heglig for 10 days, a move which coincided with air strikes against the South and raised fears of wider war. Sudan declared on April 20 that its army had forced the Southern soldiers out of Heglig, but the South said it withdrew of its own accord. Each side blames the other for damaging the oil facility, which provided about half of Sudan's oil output and is now shut down pending repairs. Sudan on Saturday ruled out UN Security Council involvement in efforts to end a month of border clashes with South Sudan, which on Saturday said it had repelled an attack by Khartoum-backed rebels. "Sudan confirms that it rejects any efforts to disturb the African Union role and take the situation between Sudan and South Sudan to the UN Security Council," Foreign Minister Ali Karti said. The African Union itself, in a decision last Tuesday, asked the Security Council to endorse its demand that the two Sudans halt hostilities in 48 hours, start talks within two weeks and complete a peace accord in three months.But Karti -- while expressing full confidence in the AU's role -- said in a statement that Security Council involvement would "give priority to a political position which... has a hidden agenda." He did not elaborate. The South Sudanese army said it had repelled an attack by rebels outside Malakal, capital of the South's Upper Nile State. "It was Sudan-supported militias that attacked SPLA (South Sudan army) positions" on Friday, Colonel Philip Aguer told AFP. But the rebels claimed in a statement that the "South Sudan Democratic Army (SSDA) launched Operation Ending Corruption and surrounded Malakal... and captured its surroundings." The Security Council on Thursday started talks on a resolution that could allow sanctions against Sudan and South Sudan if they do not follow an AU roadmap to end their fighting. A resolution drafted by the United States backs the AU decision and calls for the two sides to "immediately" halt hostilities and pull their forces back into their own territory. The roadmap also urged both sides to stop supporting rebel groups and refrain from making "inflammatory" public statements. Both nations have denied backing rebels on each other's territory. In the latest of many diplomatic calls for Sudan and South Sudan to pull back from the brink of war, the presidents of the East African Community nations urged both sides "to return to the negotiating table and find peaceful means of resolving all the outstanding issues in the Comprehensive Peace Agreement," a statement said. The EAC groups Burundi, Kenya, Rwanda, Tanzania and Uganda. South Sudan broke away from Sudan in July last year after a peace deal ended one of Africa's longest civil wars, which killed about two million people. Tensions have risen over a series of unresolved issues including the border, the future of disputed territories and oil. In a key dispute, the two sides were unable to agree on how much the South should pay to export its crude through a northern pipeline and port, leading the Juba government in January to shut its production after Khartoum began seizing the oil in lieu of payment. The poverty-stricken South said 98 percent of its pre-shutdown revenue came from oil. On Saturday it announced that China has agreed to lend it $8 billion for infrastructure development.