ISLAMABAD, Pakistan — An American drone strike killed the leader of the Pakistani Taliban in a border region of Afghanistan, Pakistani officials said on Thursday.

Pakistani intelligence officials said the group’s leader, Mullah Fazlullah, and four other senior commanders were killed Wednesday in a drone strike in the Afghan province of Kunar, near the Pakistani border. The officials spoke on condition of anonymity, but Mr. Fazlullah’s death was later confirmed by the Pakistani Ministry of Defense.

The spokesman for the United States military in Afghanistan, Lt. Col. Martin O’Donnell, confirmed that the military had carried out a drone strike on Wednesday in Kunar. He said the target was “a senior leader of a designated terrorist organization,” but he did not offer further details or confirm that Mr. Fazlullah had been killed.

Mr. Fazlullah has been the most-wanted militant in Pakistan for years. His organization has carried out hundreds of attacks against both Pakistani security forces and civilians, including an assault on a school in Peshawar in 2014 that killed 145 people or more, including at least 132 children.