A witness said at least 30 members of his Rezeigat tribe were killed in the fighting with Maaliya tribesmen over territorial claims in the Umm Rakuba district.
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 fact.
Battles between the Rezeigat and Maaliya in East Darfur state last August killed 190 people, the United Nations said at the time.
Insurgents 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.