At least 16 al-Qaeda fighters have been killed in a Yemeni airstrike in Abyan, while six soldiers were killed in clashes with fighters inside Zinjibar in the country's troubled south where the army is trying to uproot the group, military officials have said.
Yemeni war planes struck an al-Qaeda hideout about 70km from Zinjibar, the provincial capital of Abyan, which armed groups captured last year.
The bombardment killed at least 10 fighters, the officials said.
In Zinjibar itself, clashes between the two sides left six troops dead on Monday, according to the officials.
The military, backed by heavy artillery, has recently pushed into Zinjibar and regained control over some parts of the city.
The army also fired missiles at a moving vehicle on the outskirts of another southern town, Lawder, killing six fighters inside it, the officials said.
The town was controlled by al-Qaeda last year until its residents drove out the group, which has since been trying to stage a comeback.
The officials spoke on condition of anonymity because they were not authorised to speak to the media.
Monday's fighting came a day after government bombings of al-Qaeda positions across the south killed at least 30 fighters.
The attacks are part of the military's broader campaign against fighters who have seized towns and territory across southern Yemen over the past year, taking advantage of a security vacuum linked to the country's political turmoil that pushed longtime leader Ali Abdullah Saleh from power.
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The front lines are concentrated around Zinjibar and another Abyan town, Jaar, where al-Qaeda has held sway since March 2011.
If the military were to reclaim the two strongholds, it would deal a severe blow to the fighters, leaving them scattered in remote mountain areas away from urban centres.
In Jaar, armed groups sought refuge from Sunday's intense bombardment, hunkering down inside government buildings in the town centre.
Warplanes dropped leaflets urging residents not to let the fighters hide inside their homes.
A military official said one warplane on Monday missed its target in Jaar, accidentally shooting at civilians and wounding two children.
The intensifying war against al-Qaeda, which the US says is one of the network's most active branches, is a top priority for Saleh's successor and former deputy, Abed Rabbo Mansour Hadi.
Hadi took office in February in a US-backed power transfer deal and has since ramped up the fight against al-Qaeda.
On Sunday, the White House's top counter terrorism adviser, John Brennan, met with Hadi in the capital Sanaa.
Hadi's office said the Yemeni leader briefed Brennan on the army's progress against al-Qaeda in the south.
Brennan, who also met with the head of Yemen's military, reiterated Washington's strong commitment to Hadi's efforts to stabilise the country, and said the Yemeni leader is making "historical decisions during these critical times in modern day Yemen," according to a statement released by the Yemeni embassy in Washington.
Also on Monday, other Yemeni officials said an oil pipeline in Marib province was blown up about 160km east of Sanaa.
The officials, who spoke on condition of anonymity, said they suspected al-Qaeda fighters were behind the attack.
Successive attacks on oil pipelines have led Yemen's state-run oil firm safer to shut down production of nearly 50,000 barrels of crude a day.