Mullah Fazlullah, the leader of Tehreek-i-Taliban Pakistan (TTP), has been apparently killed in a US drone strike in Afghanistan's Kunar province, according to an American military official.

The official told the Voice of America on Thursday that the strike on Wednesday targeted Fazlullah. Locals in the area also confirmed the death.

"US forces conducted a counter-terrorism strike June 13 in Kunar province, close to the border between Afghanistan and Pakistan, which targeted a senior leader of a designated terrorist organisation," a spokesman for US Forces-Afghanistan, Army Lt. Col. Martin O'Donnell, also told the Voice of America, without specifying that Fazlullah was the target.

Pentagon officials declined to comment on the development.

US officials said Fazlullah directed numerous high-profile attacks against American and Pakistani targets since he was appointed the group's leader in 2013, including the December 2014 attack on the Army Public School in Peshawar that killed 151 people.

Fazlullah is also accused of ordering the 2012 attempted assassination of Malala Yousafzai, who had been advocating for the right of girls to have access to an education.

The US State Department offered a $5 million reward for Fazlullah in March, the same month Pakistani sources said his son was killed in an American drone strike on a TTP training facility.

The strike comes amid a seven-day ceasefire between the Afghan Taliban and government security forces to allow Afghan citizens to observe the last days of Ramazan and Eid peacefully.