SANAA/ADEN - US drones raided al-Qaida convoys in Yemen's southeastern province of Shabwa and central province of Marib on Saturday evening, killing at least 21 al- Qaida militants, a security official told Xinhua.

The US drone fired about three rockets on the al-Qaida convoy composed of three pick-up trucks on a desert road in Hareeb area in Shabwa province, leaving at least seven militants killed, the local security official said on condition of anonymity.

All of the three vehicles were completely destroyed following the air bombing, the official said, adding that local leading members of the Yemen-based al-Qaida branch believed to be amongst the dead.

A local resident told Xinhua anonymously that "just a few hours after an al-Qaida convoy passed through a mountainous area, we heard powerful explosions that rocked the ground."

"The al-Qaida militants were planning to attend a meeting with their senior comrades in the area," he said.

At the same time, a US warplane also attacked al-Qaida hideouts in al-Aeen area in central Shabwa, killing at least six militants, he added.

Meanwhile, a security official in Marib province told Xinhua that a US drone hit another al-Qaida convoy in Husoon area in Marib, killing at least eight al-Qaida fighters.

"Two vehicles carrying al-Qaida fighters were hit by a US drone in Husoon area," the official told Xinhua by phone, adding that "the raid came about one hour after a US drone killed seven militants in Hareeb area between Marib and Shabwa," he said.

On Sunday, a US drone strike killed al-Qaida leader Fahd al- Quso, who was wanted for links to the bombing of the USS Cole in 2000.

Earlier in the day, Yemeni armed forces surrounded an al-Qaida- held town in the southern province of Abyan, preparing to launch mass attacks on its positions, a military official said, adding that the defense ministry ordered to start the ground battle with the al-Qaida group in Jaar town and Zinjibar, the provincial capital of Abyan, on Sunday night.

The army troops have started their offensive on Saturday evening against several sites held by the al-Qaida militants in the outskirts of Jaar, leaving at least five terrorists killed, the official said.

Fighter jets of the air forces and vessels of the Yemeni navy were supporting the army forces, according to military officials.

Recently US drone carried out more strikes in Yemen, particularly in the southern regions where al-Qaida forces have their bases.