An increasing number of militants are pledging allegiance to ISIS in Afghanistan, making them a target of deadly strikes there by the U.S. unmanned aircraft.

A total of 49 militants were killed in the strikes in the eastern province of Nangarhar, which targeted the village of Mamd Dara in Achin district, where the fighters routinely held gatherings, a spokesman for the governor said.

“The first drone strike took place at 12am on Monday… the second one happened at 02:00pm,” said Ahmad Zia Abdulzai.

However, the foreign official, who asked not to be named in order to be able to speak freely, said the number of dead was believed to be closer to 25.

One of the most high profile figures to have been targeted in drone strikes so far was former Guantanamo Bay detainee Mullah Abdul Rauf, who had defected to Islamic State and was killed by a strike in southern Helmand province in February.