Twenty Yemeni soldiers and three suspected al Qaeda militants died in clashes on Saturday in the town of Jabal Ras in Yemen's western province of Hodeidah, local officials and residents said.
Fighting has flared in different parts of Yemen since the Houthis, a group of Shi'ite Muslim rebels, rose to dominance in recent months, threatening the fragile stability of a country bordering on Saudi Arabia, the world's biggest oil exporter.
Houthi forces took over the capital, Sanaa, in September and fanned out into central and western Yemen. That antagonised Sunni tribesmen and al Qaeda militants, who regard the Houthis as heretics.
Saturday's clashes broke out when suspected al Qaeda militants staged an attack.
"Twenty soldiers were killed when the al-Qaeda elements attacked an administrative building from all directions and looted four police cars," said a senior security official in Hodeidah.
He added that the central authorities had not responded to requests to beef up security in the area. Residents in the area said that the clashes were still going on.
An al Qaeda suicide bombing killed 33 people in the central province of al-Bayda last week. Days later, 30 Shi'ite rebels and 18 Sunni fighters and their tribal allies died in clashes, also in al Bayda.
Earlier this month, the Houthis took Hodeidah, site of the port of Hodeida, the second largest port in the impoverished Arabian peninsula nation after Aden.
Last month, residents and activists said al Qaeda fighters had marched into al-Odayn, a city of 200,000 in the central province of Ibb, captured the local government offices and raised their black and white flag over it.