Five African countries pledged to contribute troops to the joint African Union-U.N. force for Darfur Thursday, with Addis Ababa saying it may offer as many as 5,000 soldiers.

The development came as local media reported that dozens of people were killed in clashes this week between two Arab nomad tribes in southern Darfur.

On Tuesday, the United Nations passed a resolution to send 26,000 peacekeepers to Darfur, raising hopes for the deployment of a force that could for the first time provide real protection to civilians in the embattled region.

In Sudan, the independent daily Al Sudani and the opposition Raie Al shaab newspaper, both reporting from Nyala, the provincial capital of South Darfur, said the clashes between the Rizzaigat and the Tarjem tribes near the city left at least 82 men dead and at least 20 others injured.

It was not clear what had triggered the violence.

Farah Mustafa Abdallah, the province's deputy governor, did not deny the clashes but cautioned there was no official count of the dead.

"It is nothing new, such clashes do occur over watering spots and grazing areas, it is to be seen within that context," Abdallah told The Associated Press by phone from Nyala. He added that the situation was "now fully under control" and denied media claims it was getting out of hand.

Rae Al shaab paper quoted eyewitnesses as saying that a group of Rizzaigat tribesmen, mounted on 12 heavily armed land cruiser pickups, attacked on Tuesday a group of Tarjem men in an open area some 22 miles southwest of Nyala, where they were attending the funeral of a man slain earlier in the week in another clash of the two tribes.

The paper said 52 people were killed on the spot and 20 others were injured. Later, 30 people were killed while returning home from the funeral.

Separately, the Al Sahafa independent daily reported that clashes also occurred Monday between the two tribes near Al Gawaya, some 37 miles south of Nyala. That violence left 74 people dead and injured, the paper said.

The government in Khartoum did not comment on the reports and state media made no mention of it.

Inter-Arab tribal fighting has stepped up in South Darfur, with the motive for the attacks usually being control of agricultural and grazing land around Nyala, about 950 kilometers (600 miles) southwest of Khartoum.

This violence is separate from the conflict in Darfur, which began in February 2003 when ethnic African tribes rebelled against what they considered decades of neglect and discrimination by the Arab-dominated government.

Sudan's government is accused of retaliating by unleashing a militia of Arab nomads known as the janjaweed -- a charge it denies. More than 200,000 people have died, and 2.5 million have been uprooted.

Last month, in an apparent effort to cast himself in the role of Sudan's unifier, hardline President Omar al-Bashir visited Nyala while on a tour of Darfur. There, he appealed on the unity of all Darfurians -- ethnic Africans and nomad Arabs alike -- to join forces against tribalism and sedition.

The joint AU-U.N. force for Darfur -- long resisted by al-Bashir -- is expected to absorb and take over from the beleaguered 7,000-strong AU force already in place. The force, called UNAMID, will have a predominantly African character, as Sudan demanded.

The five African nations which pledged troops at a meeting of the African Union's Peace and Security Council in Ethiopia, included Burkina Faso, Cameroon, Nigeria, Egypt and Ethiopia. Nigeria, which already has about 2,000 troops in the AU Darfur force, is ready to send an additional battalion of about 700 solders.

France, Denmark and Indonesia have offered to contribute to the joint mission. Australia said it would send a small number of doctors and nurses, but no troops or security personnel.