Yemen's army battled al-Qaida militants in two contested southern towns, killing at least 26, the country's Defense Ministry said Tuesday, part of its weeks-long offensive against the militants.
In a separate development, sectarian clashes in northern Yemen have left at least 16 dead over the past two days.
Yemen's government has claimed for weeks that it is on the verge of recapturing Zinjibar, capital of the southern Abyan province, that fell to militants over a year ago, and that it is pushing on to the al-Qaida stronghold of Jaar. Battles in the two places rage on.
In the latest fighting, the ministry reported intense overnight clashes between government troops backed by artillery in Zinjibar and nearby Qut that left 23 dead, including Pakistani and Somali nationals.
Also, fighting in the town of Jaar left 10 al-Qaida fighters dead or wounded, military officials said. They spoke on condition of anonymity because they were not authorized to speak to reporters.
To the east of Zinjibar, four al-Qaida militants were killed and one wounded while preparing a car bomb in the coastal town of Shaqra, an official said.
On Monday, two suicide bombers tried to hit army barracks and checkpoints in the same town in an attempt to stop the military from advancing in the south, killing four army-allied militiamen. Al-Qaida has increasingly used suicide bombers and car bombs to try to halt the military offensive in the south, which started escalating May 12.
Al-Qaida-linked militants took advantage of Yemen's political turmoil last year to seize broad swaths of territory in the south. The network's branch in Yemen, known as al-Qaida in the Arabian Peninsula, was behind the failed Christmas 2009 attempt to bomb an American airliner and other attempted attacks.
In the north, sectarian clashes between hard-line Salafis and Hawthis, a Shiite group that joined last year's uprising against Yemen's president, have started up again in Saada, near the Saudi border. The city is dominated by Hawthis.
According to Hawthi spokesman Mohammed Abdel-Salam, four Hawthis were killed and six wounded in the clashes. He accused Saudi Arabia of supporting the Salafi groups against the Hawthis. A Salafi spokesman, Serour al-Wadie, said 12 Salafis were killed in the clashes.
Salafi groups live according to the ultra-conservative Wahhabi school of Islam. Saudi Arabia is the birthplace of Wahhabism.
Saudi Arabia was drawn into the conflict in November 2009 after rebels crossed the border and killed two Saudi border guards. Some 133 Saudi soldiers died in the fighting that followed.
The Hawthis fought a bloody six-year war against former president Ali Abdullah Saleh before reaching an agreement 2010 with Saleh, who then built the country's biggest Wahhabi educational institute Saada.
During the yearlong uprising that forced Saleh to transfer power to his vice president in February, more than 200 people were killed in clashes between the Salafis and Hawthis before a cease-fire was brokered.
Some Salafis follow a militant ideology similar to al-Qaida's, but they are not formally affiliated. Many Sunni extremists do not consider Shiites to be true Muslims. In recent months, al-Qaida has called on some of its forces to fight the Shiite Hawthis.