A U.S. drone strike killed seven alleged al-Qaeda suspects in Yemen's southern Shabwa province early on Wednesday, tribal sources said, amid fears of an imminent attack by the network.
The drone destroyed two vehicles in the town of Nasab and killed seven members of al-Qaeda in the Arabian Peninsula, the sources claimed.
"The shell left the cars and the militants inside in pieces," one said.
Wednesday's raid is the fifth of its kind since July 28 and brings to 24 the number of alleged suspects killed since then.
The United States and its allies pulled diplomats out of Yemen on Tuesday and stepped up security at missions across the Middle East.
Washington has closed 19 embassies and consulates in the Middle East and Africa, citing intercepted communications among militants, reportedly including an attack order from al-Qaeda leader Ayman al-Zawahiri.
Some 75 non-essential staffers at the U.S. embassy in Sanaa exited on a military plane, an American official told AFP on condition of anonymity.
While the closures span cities across the Arab world, the focus of concern has been Yemen, where American forces are fighting a drone war against al-Qaeda's powerful regional affiliate.
According to media reports, the trigger for the pullback came when U.S. intelligence intercepted messages between Zawahiri and Nasir al-Wuhayshi, the leader of al-Qaeda's Yemen offshoot, al-Qaeda in the Arabian Peninsula (AQAP).
The New York Times said Monday that last week's electronic communications revealed Zawahiri had ordered AQAP to carry out an attack as early as last Sunday.
AQAP is seen as the global Islamist militant network's most capable branch following the decimation of al-Qaeda's core leadership in Afghanistan and Pakistan in recent years.
The Yemen-based group has attempted several attacks on the United States, including a failed bid to bring down a passenger plane by a man wearing explosives in his underwear and another to send bombs concealed in printer cartridges.
The United States has launched scores of drone strikes in Yemen, where the militant group thrives in vast, lawless areas largely outside the government's control.
The United States, the only country to operate drones in the region, has sharply increased its use of them in Yemen over the past two years.
U.S. drone strikes in Yemen nearly tripled in 2012 compared to 2011, from 18 to 53, according to the New America Foundation, a Washington-based think-tank.
Critics of U.S. drone strikes have denounced the impact the attacks have had on Yemeni civilians, who have been killed or seen their homes destroyed. The United States counts any male of military age killed in drone strikes as “militants,” regardless of their actual involvement with al-Qaeda.
Yemen has listed the names of 25 al-Qaeda suspects wanted in connection with an alleged plot to launch a major attack before Ramadan ends and the Eid al-Fitr feast begins on Thursday.