KHARTOUM - Sudan's army has denied attacking the only Darfur rebel faction to sign a peace deal with Khartoum, saying tribal clashes was to blame for the fighting which killed 45 people in Muhajiriya town.

The Sudan Liberation Army (SLA) led by Minni Arcua Minnawi was the only one of three negotiating rebel factions to sign the May 2006 deal and become part of government. Muhajiriya in South Darfur is the largest town under their control.

Minnawi's faction said Monday's attack, which they said killed 45 people and destroyed half the town, was a "stab in the back of the peace deal".

And rebels said militias mobilised by the government, known as Janjaweed, along with a small number of army soldiers were still burning villages around Muhajiriya on Wednesday.

"There are planes bombing in South Darfur," said SLA Unity faction commander Abu Bakr Kadu. "The militias along with some government troops are attacking and burning civilian villages."

But the army says it was not involved in Monday's attack.

"The Sudan Armed Forces affirmed that what is happening in the Muhajiriya area is tribal clashes between the people of the area and has no relation with the Sudanese army which took no part in it," it said in a statement issued late on Tuesday, its first public reaction to the rebel accusations.

Analysts say the upsurge in fighting ahead of talks due to begin in Libya on Oct. 27 is a land grab to garner stronger negotiating positions.

As with many of the goings on in remote Darfur, the size of France, early reports on Muhajiriya were mired in confusion.

AU force commander Martin Luther Agwai, who will also command a 26,000-strong joint U.N.-AU force due to take over from the AU, had said government planes had bombed the town.

But he later said his troops had mistaken heavy artillery for aerial bombardment and said although Antonov planes were flying overhead during the attack, they had not released bombs.


PEACE TALKS

His soldiers treated two dozen wounded who came to the AU for help. Some 29 international and Sudanese aid workers were evacuated from the town.

The army statement on state news agency SUNA added Sudanese planes seen circling were monitoring the nearby area of Haskanita, as requested by the AU peacekeeping force, and were not in the Muhajiriya region.

On Sept. 29 growing tension erupted into a vicious assault on the AU base near Haskanita, killing 10 soldiers and destroying the camp in the worst attack on the force since it deployed in 2004.

The AU withdrew, asking the army to secure the formerly rebel-controlled area to help search for almost 60 missing soldiers, all but one of whom were found.

Haskanita town was burnt to the ground and all the civilians fled, with rebels reporting 105 civilians killed.

Rights group Amnesty International confirmed rebel reports of government troops massing in towns in North Darfur. Most areas north of the main towns are controlled by the rebels.

It warned an attack was imminent in a statement.

"It looks as though the Sudan Armed Forces want to attack this area before peace talks scheduled to take place in Libya before the end of the month," said Tawanda Hondora, Deputy Director of Amnesty International's Africa Programme.


OVERSTRETCHED

It said the Sudanese army planes supporting the Muhajiriya attack were painted white, the colour used by the world's largest aid operation in Darfur and the AU force.

The 26,000-strong U.N.-AU force is due to take over from the struggling and overstretched AU. Agwai says his force is outgunned and outnumbered in Darfur, with fewer than 6,000 soldiers in the area.

Amnesty says the force needs to be urgently deployed. U.N. officials say key equipment has not been pledged by Western nations.

"It will be a betrayal of the people of Darfur if, after so much struggle to get a U.N. force deployed, the international community allows the U.N. forces to suffer from the same defects that the AU forces have -- Sudan government obstruction combined with a lack of international will to give the right resources," Hondora said.

Mostly non-Arab rebels took up arms in early 2003 accusing central government of neglect. Khartoum mobilised tribal militias to quell the revolt.