At least 40 militants have been killed in a US air strike on an al-Qaeda training camp in south-eastern Yemen, local officials and medics say.
Another 25 militants were wounded when the camp in Hajr, west of the port city of Mukalla, was bombed on Tuesday.
The US defence department earlier said it estimated dozens of people had died.
Al-Qaeda in the Arabian Peninsula (AQAP) has exploited the current conflict in Yemen to expand the territory under its control.
Over the past year, the Houthi rebel movement and military units loyal to the former president have been battling a US-backed, Saudi-led coalition supporting the internationally-recognised government.
Almost 6,300 people, half of them civilians, have been killed in the fighting.
‘Denying AQAP safe haven’
The US has continued its campaign of drone and missile strikes against AQAP throughout the conflict, resulting in the deaths of a number of senior figures, including the group’s leader Nasser al-Wuhayshi in June and its combat operations chief Jalal Baleedi last month.
Pentagon spokesman Peter Cook said the training camp targeted on Tuesday was located in a mountainous area and was being used by more than 70 militants.
“We continue to assess the results of the operation, but our initial assessment is that dozens of AQAP fighters have been removed from the battlefield,” he added.
“This strike deals a blow to AQAP’s ability to use Yemen as a base for attacks that threaten US persons, and it demonstrates our commitment to defeating al-Qaeda and denying it safe haven.”
Mr Cook gave no further details about the attack, but Yemeni security officials and witnesses told the Associated Press that it hit a former military base about 75km (47 miles) west of Mukalla, which AQAP seized along with most of the surrounding province of Hadramawt last year.
Medics and a local official told the Reuters news agency that as many 50 militants had been killed in the attack, while a tribesman told AP that at least 40 had died.
“The planes struck as al-Qaeda people stood in line to receive their dinner,” the local official said.
Tribal sources told the AFP news agency that wounded militants were taken to a hospital in Mukalla, and residents of the city reported seeing dozens of militants rushing to the facility to give blood.
The US considers AQAP as one of the deadliest offshoots of the jihadist network founded by Osama bin Laden. The group attempted to bomb a US-bound airliner in 2009 and claimed responsibility for the attack on the offices of the magazine Charlie Hebdo in Paris last year that left 12 people dead.