The Interior Ministry said the rebels had opened fire on members of the Ben Aziz tribe, killing three tribesmen and wounding three others including a passerby.

Yemen, struggling to stabilize a fractious country, has come under international pressure to quell domestic conflicts in order to focus on quashing Al-Qaeda elsewhere in the Arabian peninsula state.

The Shiite rebels said they attacked the Ben Aziz tribesmen in response to an earlier assault on the same day when the tribesmen opened fire on a market and wounded three people.

That attack, according to a local official, was in retaliation for a tribe member's killing last week that they blamed on the rebels.

The rebels said on their website that the tribe had also cut the main road between their stronghold in Saada and the capital Sana’a.