Yemeni militia have killed an Al-Qaeda prisoner who tried to escape but a local militant leader managed to flee as they found an explosives lab in a separate incident, a militia source said on Saturday.

In another development, two soldiers were killed and three wounded in an ambush, an official said.

"A member of Al-Qaeda was killed on Friday when he tried to escape from a jail controlled by the Popular Resistance Committees," in the southern town of Jaar, the source in the pro-government militia said.

Separately, militiamen searching a house in Jaar discovered a bomb-making factory and seized a number of explosives belts.

Al-Qaeda's leader in Zinjibar, the nearby capital of Abyan province, managed to escape from the house, the source said. The man was identified as Jalal Belaidi, alias Abu Hamza.

Meanwhile, the two soldiers were killed and three others hurt when gunmen ambushed their vehicle in a desert region of the eastern province of Hadramawt on the road to neighbouring Marib province.

Taking advantage of a central government weakened by an Arab Spring-inspired uprising last year, Al-Qaeda-linked militants had captured Zinjibar, Jaar, Shuqra and other towns across Abyan.

Government forces launched an all-out offensive in May and recaptured the towns the following month.