ISLAMABAD, Pakistan — The Pakistani Taliban have confirmed the death of their deputy commander in an American drone strike in Afghanistan last week. The commander’s death is a blow to the militant group that has been responsible for deadly suicide bombings and terrorist attacks in Pakistan for over a decade.

The commander, Khan Sayed, who also went by the name Khalid Sajna, was the No. 2 leader of the Pakistan Taliban. He also led his own breakaway faction of fighters from the Mehsud tribe, which inhabits the rugged, semiautonomous South Waziristan region along the border with Afghanistan.

Pakistani intelligence officials thought he had been killed in a 2015 American drone strike and were still trying to confirm this latest report of his death. But they saw credibility in this claim because the Taliban announced his death and the appointment of a successor.

His death could force more Mehsud Taliban members to surrender to the Pakistani military “as they have lost the only unifying figure in their ranks,” said Saleem Safi, a senior analyst and a Geo News talk-show host. It could also lead to infighting between the Pakistani Taliban’s factions over the group’s leadership, he said.