At least 34 people, mostly Islamist militants, were killed near the southern Yemeni city of Lawdar on Friday in clashes between government forces and an al-Qaeda-linked group, official and tribal sources said.
Yemen's military launched an offensive five days ago against Islamic insurgents who attacked a military camp outside Lawdar.
It intensified operations on Friday, sending an elite anti-terrorism unit from the capital Sanaa to join the fight, according to local officials.
The Defence Ministry said 28 militants were killed during clashes west of Lawdar, according to a statement on its website. A local official and tribal sources said three militants and three tribesmen fighting alongside the government forces were killed in separate clashes outside Lawdar.
The clashes brought the death toll since fighting erupted on Monday to nearly 200 people, according to local sources.
A local official said the Yemeni air force bombed two sites held by Ansar al-Sharia (Partisans of Islamic Law), a group affiliated with al Qaeda, but no casualties were reported.
Another official said security forces arrested a senior al Qaeda leader from Lawdar.
The Islamist group said in an emailed statement on Friday its fighters killed 37 tribesmen fighting for the government over the past two days, including seven in an attack on Friday.
It also said its militants late on Thursday launched a rocket at the house of a security chief in the southern city of Aden, killing three security officers during ensuing clashes.
The group seized control of a significant amount of territory in Abyan during the turmoil that led to the replacement of President Ali Abdullah Saleh by his deputy.
Saudi Arabia and the United States hope the political deal will prevent al Qaeda from getting a foothold near oil shipping routes.
The conflict with Islamists in the south is one of several challenges facing the new president, Abd-Rabbu Mansour Hadi, who took office vowing to fight al Qaeda.
(Reporting by Mohammed Mukhashaf; Writing by Mahmoud Habboush; Editing by Janet Lawrence)