Sudanese rebels on Tuesday said they had resisted for the second time in two weeks an army attempt to retake an area seized during a surprise strike into a previously peaceful region.

They said they remained in control of Abu Kershola in South Kordofan state, where the defence ministry late Monday reported "intensive fighting on the ground and by air."

Insurgents from the Sudan Revolutionary Front (SRF) coalition said they seized the government garrison at Abu Kershola on 27 April during attacks on several nearby areas, including Umm Rawaba, the second-largest town in North Kordofan state.

The strike was the rebel coalition's first joint-forces operation.

Arnu Ngutulu Lodi, spokesman for the Sudan People's Liberation Movement-North (SPLM-N), which belongs to the SRF, said the fighting came to a halt Monday and insurgents were still in control of Abu Kershola.

But on Monday night a defence ministry spokesman said "the fighting is still going on".

Rebels said last week they repulsed an initial attempt to retake the town, a claim denied by the army.