Scores of people have been killed in fresh clashes between two Arab tribes in Sudan's troubled western region of Darfur, witnesses from the rival camps have said.

One person said at least 30 members of his Rezeigat tribe were killed in the fighting, in which heavy weapons were used, with Maaliya tribesmen over territorial claims in the Umm Rakuba district, the AFP news agency reported.

On the other side, a Maaliya witness said at least 40 members of his tribe were killed, although there was no independent confirmation of the losses.

Battles between the Rezeigat and Maaliya in East Darfur state last August killed 190 people, according to the UN.

Hundreds more people died in battles between other tribal and ethnic groups, most of them Arab, in Darfur last year.

Fighters from non-Arab ethnic groups in Darfur rose up 11 years ago against what they said was the domination of Khartoum's power and wealth by Arab elites.

In response, the government turned to Janjaweed militia recruited from Arab tribes, who have since been incorporated into official paramilitary units.

Militias vying for pasture and water for their livestock in the vast arid region have since turned on each other, and sometimes against the government, while violent crime has increased.

Source: Agencies