Yemeni tribesmen opposed to President Ali Abdullah Saleh said they stormed a military base near the capital used by troops loyal to Saleh on Monday and made off with weapons.
Hameed Asim, a leader of tribesmen who have skirmished with troops from the Republican Guard led by Saleh's son, said tribal fighters killed several troops and lost seven of their own in a raid on the base north of the capital, before withdrawing.
The attack was the latest in a series of running battles between tribesmen in the Arhab region north of the capital Sanaa and forces backing Saleh, who is clinging to power despite 10 months of protest demanding his overthrow and a slide towards civil war on the borders of oil giant Saudi Arabia.
It follows reports of progress in talks to implement a plan crafted by Yemen's Gulf neighbours to ease Saleh from power, which opposition political factions say have been stuck on the question of formal command of the national army.
The political standoff in Yemen has re-ignited conflicts with separatists and militant Islamists who have seized territory in the south, alarming Riyadh and Washington, which funded Saleh as part of its campaign against al Qaeda.
Saleh has wriggled on three occasions out of the power handover plan backed by the Gulf Cooperation Council and mirrored in a U.N. Security Council resolution, which a United Nations mediator is trying to put in place.
The crisis over Saleh's fate has brought almost complete economic paralysis and periodically halted oil production in one the world's poorest countries, which depends on crude exports for revenue to fund imports of staple foodstuffs.
(Reporting by Mohammed Ghobari, Writing by Joseph Logan; Editing by David Stamp)