The military officials from Shabwa province said that an unmanned US drone carried out the attack on a vehicle carrying seven militants in the district of Azan. The officials said four were killed, while three were critically wounded and under treatment in a nearby Al-Qaeda-run clinic in Shabwa.
A security official said the attack may have killed leading figures in the group, who were attending Friday prayers and left together. He had no further details.
A second airstrike yesterday, just a few kilometers from the first strike, hit a building believed to be used by Al-Qaeda near a main market in the town of Azan. Four residents were wounded, said medical officials.
There was no immediate comment from US officials, but Washington has carried out deadly airstrikes in Yemen in the past. Last year, a US drone strike killed US-born militant cleric Anwar Al-Awlaki and a second American, Samir Khan, who edited Al-Qaeda's Internet magazine.
Last month, Al-Qaeda-linked militants publicly executed a Yemeni in Azan who they suspected of collaborating with the United States by planting electronic devices that help US drones strike militant positions.
Al-Qaeda in the Arabian Peninsula, as the branch is known, was believed to have plotted two failed attacks on American soil.
The group has taken advantage of a year of turmoil in Yemen to seize control of several regions in the south. Militants overran cities as the government focused its efforts on protecting the regime in the capital during a year of protests against former President Ali Abdullah Saleh.
Saleh's replacement, Abed Rabbo Mansour Hadi, has made fighting Al-Qaeda one of his top priorities, but many Yemenis accuse the ousted president, whose loyalists are still influential in the military and in government bodies, of undercutting security operations and the new president's authority.
Also yesteray, suspected Al-Qaeda militants opened fire on a powerful tribal head who sits in Yemen's upper house of Parliament as he was coming out of a mosque in the southern city of Aden. His two bodyguards were killed in the attack but he was unharmed, according to medical officials.
Mohammed Hussein Ashal's tribe fought Al-Qaida last year in Mudya district in Abyan province near Aden, kicking them out of several towns.
Militants killed Ashal's son last year in the capital Sanaa, and have also targeted other officials in Aden, shooting dead an intelligence chief in December.
