At least 10 tribesmen were killed in northern Yemen during clashes with Shiite rebels, the Defence Ministry said on Wednesday, less than two weeks before a presidential election aimed at ending a year of unrest.
An uprising against outgoing President Ali Abdullah Saleh has severely weakened central government control over swathes of Yemen, allowing the rebels, known as Houthis, to seize the governorate of Saada, which borders oil-exporter Saudi Arabia.
The latest clashes took place in Hajja province, which neighbours Saada, after tribesmen accused the Houthis of trying to grab more territory.
"Security reports say there was fierce fighting between the two sides ... The clashes between the Houthis and the tribesmen took place in and around a technical college and other areas," said a statement on the Defence Ministry's website.
The number of Houthis killed was not known.
Saudi Arabia briefly fought the Houthis in Saada after they seized Saudi territory in 2009.
The Houthis have said they will boycott an election later this month to pick a successor to Saleh, who is in the United States receiving medical treatment for injuries sustained during an assassination attempt last year.
Saudi Arabia and the United States fear protracted political upheaval in the impoverished state is giving Al-Qaeda's regional wing room to gain a foothold near oil shipping routes through the Red Sea.