A Yemeni army officer and two of his troops were killed in an ambush by gunmen near the southern port city of Aden on Saturday, military sources said. They said the unidentified assailants opened fire with automatic weapons on a jeep outside the town of Daleh. Apart from the military casualties, two civilians were wounded, witnesses said. Yemen authorities have been confronted by an Al-Qaeda resurgence in the south and east of the country as well as a southern secessionist movement and a revolt by Shiites in the north.