Updated

Clashes between tribes of Arab nomads and ethnic African farmers competing for Darfur's resources have killed 150 people in the last two weeks, according to the United Nations mission to Sudan.

The U.N. mission also said that 64 people among the latest wave of refugees chased by separate pro-government janjaweed militia raids have been diagnosed with leprosy.

A joint team of U.N. and Sudanese officials, sent to investigate the tribal fighting, reported that 101 Targem farmers were dead or missing around the South Darfur locality of Bulbul, as well as 40 Rezeigat nomads.

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Some 12 villages belonging to the Targem were also burnt to the ground, and refugees have started pouring into the South Darfur camps, the U.N. said in a statement issued late Thursday.

"The government deployed a joint military and police force with patrols" to pacify the area, the statement said.

The fighting illustrates the spiraling violence in Sudan's remote Darfur region, where more than 200,000 have died and 2.5 million fled their homes since 2003, when ethnic African rebels took arms against the central Khartoum government, charging it with neglect.

The government is accused of having unleashed in response the janjaweed militias of Arab nomads, blamed for the worst atrocities in the conflict.

To the west of the region, "consistent attacks from Arab militias" against villages near the border with Chad chased more civilians into refugees camps, the U.N. said.

At least 64 of these new refugees were found to suffer from leprosy, the U.N. said.

While there have been "a few pockets of leprosy" endemic in Darfur, the new refugees who arrived in the Zaleingi refugee camp are one of the largest group case diagnosed, World Health Organization workers said.

"They have been settled separately from the rest of the camp and are receiving medication," WHO's doctor Mohammed Abdi said on the telephone from West Darfur.

U.N. agencies and aid groups said earlier this week they feared worsening violence would "irreversibly" jeopardize efforts to improve the health of some 4 million vulnerable people in Darfur, many of whom live in inaccessible areas such as the border villages recently attacked by janjaweed.

Several other tribal militias also plague this vast, arid region of western Sudan, where scarce resources regularly pit nomadic tribes against sedentary ones.

Separate fighting earlier this month between the Habania Arabs and Falata ethnic Africans claimed some 200 lives, also in southern Darfur, the Sudanese justice minister said.

Violence has only worsened in Darfur since last May, when the government and one rebel group signed a peace agreement.

Khartoum opposes a Security Council resolution to replace an overwhelmed African Union peacekeeping force in the region with some 22,500 U.N. peacekeepers and police.

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