Yemen Clashes Kill 13 Al-Qaida Militants, 4 Troops Yemen military officials say the latest fighting to uproot al-Qaida from the country's south has killed 13 militants, as well as four soldiers and two militiamen fighting alongside the army. The officials say the 13 al-Qaida fighters died Wednesday as they tried to recapture a strategic hilltop overlooking the town of Lawder in Abyan province from where they were driven out a day earlier. The two militiamen died in that battle. Meanwhile, a military hospital official says four soldiers died in fighting in the provincial capital Zinjibar. All the officials spoke on condition of anonymity because they are not authorized to talk to the media. Yemeni officials say U.S. troops are for the first time helping direct a four-front assault on al-Qaida strongholds launched Tuesday. SANAA, Yemen (AP) - Yemeni warplanes and troops backed by heavy artillery waged a four-front assault Tuesday against the strongholds of al-Qaida militants in the south, with U.S. troops for the first time helping direct the offensive from a nearby desert air base-turned-command center. Yemeni military officials said dozens of U.S. troops were operating from al-Annad air base, about 65 kilometers (45 miles) from the main battle zones, coordinating assaults and airstrikes and providing information to Yemeni forces. The officials said it was the most direct American involvement yet in the country's expanding campaign against al-Qaida's branch in Yemen, which has been blamed for directing a string of unsuccessful bomb plots on U.S. soil from its hideouts in the impoverished country at the tip of the Arabian Peninsula. Most recently, this month it emerged that the CIA thwarted a plot to down a U.S.-bound airliner using a new, sophisticated explosive to be hidden in the bomber's underwear. But the planned bomber was actually a double agent who turned the device over to the U.S. government. The offensive is the most concerted yet aiming to uproot al-Qaida militants who since last year have held a swath of territory, including the provincial capital Zinjibar and several other towns, in the south of the country. One Yemeni military official said the country's defense minister and an American general, whom he did not identify, were jointly overseeing the assault. In a crescent-shaped assault on Zinjibar, Yemeni troops pushed into the center of the city, though they did not outright control it, one official said. Military helicopters flew over the city for the first time in an indication militants had lost their heavy weaponry capable of shooting down the helicopters, the official said. The troops "can for the first time catch a glimpse of the torched government buildings" that al-Qaida's fighters had hunkered down in during recent battles, the official said. Al-Qaida militants seized Zinjibar, the capital of Abyan province on the Arabian Sea coast, last year while the country was mired in the political turmoil of the popular uprising against then-President Ali Abdullah Saleh. The militants also took control of several other nearby towns. Tens of thousands of residents fled the area.