Three strikes on Tuesday night targeted Pakistani Taleban militants in one of their strongholds in the Tirah Valley in the northwestern Khyber region on the Afghan border.
"We have reports that 40 to 45 terrorists were killed," a security official told Reuters. Taleban insurgents often deny official death tolls of militants.
Pakistani forces have stepped up air strikes in Khyber and adjoining Pashtun tribal lands in recent months against activists who fled military offensives in the Taleban strongholds of Swat and South Waziristan bordering Afghanistan last year.
Air strikes could undermine efforts to win over civilians for the fight against the Taleban.
"Some of the families were living in the vicinity of these hideouts and they were also among the dead," said the security official.
Rehan Khattak, a senior government official in Khyber, said six civilians, including women and children, were killed in one of the strikes and they had nothing to do with militants.
"Four people were also wounded. They were members of Kokikhel," Khattak told Reuters, referring to a pro-government Pashtun tribe which dominates Khyber.
Anar Bacha, 32, one of the wounded, said they were innocent.
"We are going to our home in a cab when all of a sudden planes appeared and began targeting us," he said. "We are innocent. We are Kokikhels. We are not terrorists."
In April, up to 50 members of the same tribe were killed in an air raid in Tirah after they were mistaken for Taleban, prompting an apology from Pakistan army chief General Ashfaq Kayani.
Khyber is a key route for US and allied convoys carrying supplies for troops fighting militants in Afghanistan. Fighters frequently attack these convoys, forcing the United States to look at developing alternate routes.
