A dozen Arab tribal leaders from Sudan's western region of Darfur have pledged allegiance to paramilitaries at war with the army -- a move analysts warn could tip the scales in the months-long conflict.
The war between army chief Abdel Fattah al-Burhan and Mohamed Hamdan Dagalo, better known as Hemedti, who commands the paramilitary Rapid Support Forces (RSF), has wreaked havoc on Darfur, where experts fear a widening ethnic divide could spell more violence.
In a video released Monday, leaders from seven of South Darfur state's main tribes urged their members to desert the army and fight instead for the rivalling RSF.
"This announcement will have a massive impact" on the war in Sudan, which has killed nearly 3,000 people, said veteran local journalist Abdelmoneim Madibo.
"Like in El Geneina, it will divide South Darfur between Arabs and non-Arabs," he told AFP, referring to the West Darfur capital which has been the scene of major bloodshed and ethnically targeted attacks.
The RSF paramilitary group traces its origins to the Janjaweed -- feared Arab militiamen who committed widespread atrocities against non-Arab ethnic minorities in Darfur starting in 2003.
Many fear a repeat of history in the latest war, with residents and the United Nations reporting civilians being targeted and killed for their ethnicity by the RSF and allied militiamen.
Dividing Darfur
Both sides have long courted young men in Darfur, which is home to a quarter of Sudan's population.
But experts point out that while the war has already taken on an ethnic dimension in the region, it has yet to impact the makeup of the forces, which are comprised of both Arab and non-Arab groups.
The army's second-in-command in both Nyala and neighbouring East Darfur are generals from the Arab Misseriya tribe. Meanwhile, the armed forces count several officers from the Rizeigat tribe -- Hemedti's own -- among their ranks.
The leaders of both tribes appeared in Monday's video, rallying support for the RSF.
There has yet to be an exodus from the army's ranks. However, analysts fear the tribal push could bring about further ethnic stratification.
Darfur specialist Adam Mahdi said the announcement carries tremendous weight, saying the tribal leaders represent "the real government" in the region and without them, "the army holds no respect or legitimacy".
The point of Monday's video, he told AFP, was to draw a line in the sand, cut off army recruitment and "clearly state the allegiance" of these tribes to the RSF.
The army could find itself facing a broad united front "pushing it out of South Darfur, where most of its bases have fallen," Mahdi told AFP.
The temptation could be "to arm other tribes and launch a proxy war," he added.
A military source dismissed the call to arms as "a media stunt" by tribal leaders "out for their own interests", speaking to AFP on condition of anonymity because he is not authorised to speak to the media.
For the moment, he said, those interests converge with those of Hemedti -- who is "trying to prove he has tribes' support".
But in both southern and eastern Darfur, where Arab tribes are the majority, local fighters have joined the fray on the RSF's side, according to several residents.
Adam Issa Bishara, a member of the Rizeigat tribe, told AFP he is preparing to go and fight for the RSF in Khartoum.
"They're our cousins, we can't abandon them," he said.
The RSF have not announced how many of their forces have been killed under near-daily air strikes from the armed forces in Khartoum.
Mere hours after Monday's video appeared online, witnesses in a West Darfur town reported an attack "by armed men from Arab tribes supported by the RSF".
Activists in West Darfur have accused the RSF of "executing" civilians for being part of the Massalit tribe, one of the major non-Arab ethnic groups in the region,
Rights defenders, tribal leaders and international groups have condemned the assassinations of Massalit officials in the West Darfur capital of El Geneina, which has seen some of the worst fighting in the current war.
Observers say the centre of fighting in Darfur -- a region the size of France -- is shifting to Nyala, the capital of South Darfur and Sudan's second-largest city.