The janjaweed so far have not respected the new peace agreement, attacking rebel-held towns in the area of Kutum in northern Darfur and Shearia in South Darfur, killing dozens of people.

They are divided into the Abbala (camel-herding) Rizeigat, who live in northern Darfur and Chad, and the Baggara (cattle-herders) who inhabit south-east Darfur.

Sudanese rebels said Thursday that government troops and militias had killed more than 50 people in an attack in northern Darfur, Reuters reported.

In northern Darfur in recent days, the two factions of the Sudan Liberation Army have been fighting each other, battling for territorial dominance ahead of a peace deal, diplomats and aid officials said.

Drought from the mid-1970s to early 1980s led to massive immigration from northern Darfur and Chad into the central farming belt.

In July 1976, one thousand followers of Sudanese opposition leader Sadiq al-Mahdi left the oasis and stormed Khartoum after crossing northern Darfur and Kordofan.

Despite a peace treaty signed this spring with one of the rebel groups, the killing continues, especially in northern Darfur, and many diplomats and aid experts have forecast a humanitarian disaster.

The scale of climate change impacts recorded in northern Darfur is almost unprecedented: the reduction in rainfall has turned millions of hectares of already marginal semi-desert grazing land into desert.

Zam Zam, a former village in northern Darfur that has been transformed into a sprawling camp of people on the run from war, is one place that illustrates the new Darfur.

Salim, 13, from northern Darfur: "We returned from school. . . . We are all looking, and not imagining bombing.