Tribal officials say that Shiite Hawthi rebels have defeated one of Yemen's most dominant tribes after weeks of fighting between the two groups over territory in the northwest part of the country, in a landmark victory for the separatists.

Hawthis seek independence from the country's Sunni-aligned government and have been waging a campaign to expand their reach beyond the northwest mountains toward the capital, Sanaa.

In recent days, at least 150 militants have died in battles over the villages Houth and Khamra in Amran province. A government-backed cease-fire failed to stop the fighting.

Hawthi leaders announced the victory early Sunday.

Gameel al-Hashidi, a leader of the ultraconservative Sunni Hashid tribe, told The Associated Press that the area was completely under Hawthi control.