Afghan Taliban leader Mullah Akhtar Mansour has probably been killed in a US air strike, US officials say.
He and another male combatant were targeted as they rode in a vehicle in a remote area of Pakistan close to the Afghan border, the officials said.
The Pentagon has confirmed it targeted Mansour in strikes but said they were still assessing the results.
Mansour assumed the leadership in July 2015, replacing Taliban founder and spiritual head Mullah Mohammad Omar.
The operation took place near the town of Ahmad Wal at around 15:00 (10:00 GMT) on Saturday and was authorised by President Barack Obama.
Both Pakistan and Afghanistan were informed about the strike shortly after it took place, the White House said.
“We are still assessing the results of the strike and will provide more information as it becomes available,” said Pentagon spokesperson Peter Cook.
An unnamed Taliban commander told the Reuters news agency: “We heard about these baseless reports but this not first time. Just wanted to share with you my own information that Mullah Mansour has not been killed.”
The death of Mullah Akhtar Mansour, if confirmed, would be a big blow for the Taliban.
He was gradually tightening his grip on the movement by bringing into his fold other leading Taliban members, including a son and a brother of his predecessor Mullah Mohammed Omar, and by launching large scale attacks on Afghan security forces.
Under his leadership, the Taliban managed to capture an important city last year for the first time in 15 years.
Mansour also managed to silence the splinter Taliban group under Mullah Muhammad Rasool, which challenged his leadership, and is credited by his followers for containing so-called Islamic State in Taliban areas.
A vacuum created by his death would once again trigger a leadership struggle.
False rumours have often surrounded Taliban leaders.
Omar died in 2013 but this was only confirmed by the Taliban two years later, while Mansour was reported to have been killed in a gun battle last year, something dismissed by the Afghan government.
Mansour’s appointment as Taliban chief was disputed, with a rival group selecting their own leader.
The Pentagon’s statement said Mansour was actively involved with planning attacks “presenting a threat to Afghan civilians and security forces, our personnel, and Coalition partners”.
The Taliban have made gains since international troops withdrew from an active fighting role in 2014.
Nato forces are increasingly being deployed in battle zones to support Afghan forces fighting the Taliban.
Read more: http://www.bbc.com/news/world-asia-36351990