The Yemeni Air Force on Tuesday killed a high-rank leader of the Yemen-based al-Qaida wing along with other four militants in southern troubled province of Abyan, a local official told Xinhua.

"Mujaheed Abu Ali, the emir of al-Qaida in the Arabian Peninsula (AQAP) in Abyan's second city of Jaar, was killed along with other four militants when a missile from Yemeni fighter jet hit the terrorist car in a road between Jaar and Zinjibar," the official said on condition of anonymity.

Residents of Zinjibar said that Yemeni security and armed forces backed with tanks and mortars have been shelling the city since Sunday. They said most of the residents fled the city.

Meanwhile, the Defense Ministry's online website said late on Monday that 21 security and military personnel were killed during the previous two-day battles with AQAP fighters.

On Saturday, the AQAP declared Zinjibar as the capital of their newly-established Taliban-style Islamic Emirate after the militants almost controlled most parts of the province, 480 km south of the capital Sanaa.