Muhammad Ali Adam comes from one of the most feared tribes in south Darfur, the Arab Falata. As a Janjawid fighter he helped his militia to rape, loot and murder its way through village after village. Yet he is among a growing number of Arab gunmen switching sides as they grow disillusioned with the Khartoum Government.

“If I remember the actions which we did, I feel very sorry and sometimes I cry,” he said, sipping sweet, black tea with half a dozen of his new comrades from the Sudan Liberation Army (SLA), deep inside Jebel Mara, the mountainous stronghold of the anti-Khartoum rebels.

Once they would have tried to kill each other.

Commander Adam, with his dark tan and Khartoum-issued, Chinese-made Kalashnikov, cuts an unlikely figure as a rebel commander. Yet he now ventures regularly into the hillside town of Gorolang Baje – home to the Fur people that gave Darfur its name – to take orders from his new superiors, who used to be his foes.

His presence here is a sign that the widely accepted view of the Darfur conflict is breaking down. No longer is it a case of rebels drawn from the black, farming tribes pitted against an Arab-dominated Government and their light-skinned Janjawid allies.

Defections such as that of Commander Adam have eased fighting in some parts of Darfur. But the increasingly complex picture makes prospects of a resolution even more difficult, according to analysts.

Darfur is riddled with tribal tensions. In places, Arab tribes have turned on one another as they compete for land plundered from non-Arab tribes. Several Arab tribes have kept out of the conflict altogether.

And at the end of last year a new rebel grouping emerged from Arab tribes: the Popular Forces Army.

Splits among rebel groups appeared last year after the signing of the Darfur Peace Agreement. One arm of the SLA, which signed up for peace and is now allied to the Government, is spearheading an offensive against its old comrades who are holed up in Jebel Mara.

“The level of complexity has always been there beneath the surface,” one aid official said in the south Darfur capital of Nyala. “What we are seeing though is the divisions come to the surface, and overall security is getting worse.”

Commander Adam, 23, who commands a unit of 70 nonsignatory SLA soldiers, is clear about why he split from Khartoum seven months ago. He said that the Government promised his people land amid the fertile slopes of Jebel Mara, where apple orchards and orange groves prosper far from the dusty, desert plains that comprise the rest of Darfur.

But four years on, he said he wondered why he took up arms. He found himself fighting people from the Fur tribe – a people whose language he spoke and had always considered good neighbours. Now, as he listed the villages he helped to burn – Hamada, Durbo, Baliserif, Debenera, Jafaina – he said that he felt only regret.

Hamis Muhammad Adam, the political officer of the SLA in Gorolang Baje, said: “There were so many serious things, sad stories, burning villages, killing people, but if someone is wrong and has discovered that they are wrong, what can we do? We can only forgive them.”

The shifting allegiances make peace an even more pressing priority, said Muhammad Guyo, of the Institute for Security Studies in Nairobi. “If things continue as they are, with rebel groups fragmenting and other militias switching sides, then it becomes more and more difficult to imagine a resolution.”

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