One hundred people, including Chadian soldiers, have been killed in tribal clashes in the Darfur region of western Sudan.

"The number of casualties has grown to 100" after battles between the Misseriya and Salamat tribes, Sudan’s Radio Omdurman reported in a brief bulletin sent by SMS on Saturday.

The Salamat and the Misseriya are two rival groups which have been fighting each other for many years. The fighting between the two groups has escalated this month in southwestern Darfur.

The fighting between the two groups continued on Saturday around the Umm Dukhun area, near the Chadian border, claiming the lives of over 50 people from both sides, AFP quoted a Misseriya leader as saying.

Also on the same day, a humanitarian source, who spoke on condition of anonymity, said a number of Chadian soldiers were killed in a fighting with Salamat tribesmen around Umm Dukhun on Thursday.

"Chadian deaths are confirmed," said the source, adding, they were killed "most likely inside Chadian territory."

"They were eventually repulsed by the mixed Chad-Sudan forces, and pushed into Chad where the forces chased them for a while," the source added, referring to the Salamat tribesmen.

Sudanese and Chadian soldiers jointly patrol their border region.

Reports say around 200 people have lost their lives in the clashes between the two groups since April.

The UN Office for the Coordination of Humanitarian Affairs (OCHA) says tribal conflicts and insurgency have displaced at least 460,000 people in Sudan's Darfur this year.

On November 13, Sudanese Defense Minister Abdelrahim Mohammed Hussein said tribal violence in Darfur has eclipsed rebel activity as the main security threat in the region.

On November 12, African Union-United Nations Hybrid Operation in Darfur, known as UNAMID, expressed “grave concern” over recent reports of violence among Misseriya, Taisha, and Salamat tribes in parts of Central Darfur State.

Sudan accuses South Sudan, which seceded from the Republic of Sudan in July 2011, of supporting anti-government rebels operating in the Darfur region and the states of Blue Nile and South Kordofan.

South Sudan became independent on July 9, 2011, after decades of conflict with the North.