At least two Yemeni soldiers and a militant were killed in a clash when militants tried to attack a military compound in southern Yemen on Saturday, the Defence Ministry said on its website.
The 26 September website said al Qaeda militants approached the compound in Lawdar town with suicide belts, hand grenades and explosive devices, when soldiers from the 115th Infantry Brigade and members of neighbourhood patrols confronted them.
"They confronted them and killed one of them who carried Saudi nationality, injured another and arrested two," the website said, adding that two soldiers were also killed in the clash and a third was wounded.
Yemen is home to one of al Qaeda's most lethal franchises, al Qaeda in the Arabian Peninsula. The group has focused much of its attacks in Yemen on security forces.
Stabilising Yemen is an international priority given its proximity to top oil exporter Saudi Arabia.
The country, which has been hit with lawlessness since 2011 when mass protests forced longtime leader Ali Abdullah Saleh to step down, is also grappling with an offensive by a Shi'ite Muslim Houthi movement to extend its control over the north.
Separately unknown assailants blew up an oil pipeline in southeast Yemen late on Friday, Yemeni news website, al-Mukallah Star, reported. Tribal sources confirmed the attack.
The pipeline has a capacity of 120,000 barrels per day and has been blown up several times in the past, disrupting an important source of revenue for the impoverished state.
Disgruntled tribesmen often carry out such attacks to pressure the government to provide jobs, settle land disputes or free relatives from prison.