Fifty-five Yemen-based al-Qaeda militants, including three senior members, were killed in an hours-long series of air strikes on a southern training camp operated by the group, the Associated Press quoted the country's interior ministry as saying, Al Arabiya News reported.
The operation, which kicked off Sunday and is believed to have involved U.S. drones, targeted a sprawling training camp of Al-Qaeda in the rugged mountains of Mahfad between Abyan, Shabwa and al-Bayda provinces, the news agency said.
AP quoted security officials as saying the camp's infrastructure was destroyed.
The operation came a day after an air strike killed 10 al-Qaeda militants and three civilians in central Yemen.
In a statement on its website, the defense ministry quoted an official source on the High Security Committee as saying that Sunday's air strikes were based on information that "terrorist elements were planning to target vital civilian and military installations," Reuters news agency reported.
The source did not specify the nature of the air strikes, saying only that the strikes happened in the framework of "efforts the Yemeni government is exerting to combat terrorism," the agency said.
Al-Qaeda in the Arabian Peninsula (AQAP), based in Yemen, has been targeted by U.S. drone attacks in the past, leading to the death of several suspected AQAP figures, including, in 2011, Anwar al-Awlaki, a U.S.-born Islamist cleric accused of links to the attempted bombing of a Detroit-bound airliner in 2009 and U.S. cargo planes in 2010.
Although the U.S. acknowledges using drone strikes to target AQAP in Yemen, it does not comment on the practice.
U.S. congressman Michael McCaul of Texas, the chairman of the House of Representatives Committee on Homeland Security, said AQAP posed "probably the greatest external threat to the homeland itself.
"And so I think the fact the administration now is going aggressively against these terrorists ... is a very positive sign," said McCaul, appearing on the Sunday morning ABC News program "This Week."
Yemen has been unilaterally fighting AQAP but the group, which has attacked military targets, tourists and diplomats in the country, is proving difficult to defeat.