The leader of Islamic State's branch in Afghanistan and Pakistan has been killed in a US drone strike, the Pentagon says.
The death of Hafiz Saeed Khan on July 26 is a blow to efforts by Islamic State - also known as ISIS or Daesh - to expand from its heartlands in Syria and Iraq into Afghanistan and Pakistan, already crowded with jihadist movements including the Taliban and al Qaeda.
The fatal strike follows the killing of Afghan Taliban leader Mullah Akhtar Mansour in a US drone attack in Pakistan in May.
However, Afghanistan's 15-year-old war grinds on with no clear victory in sight.
Taliban fighters have been threatening at least two provincial capitals this (northern) summer, in Helmand and Kunduz, and a US government report said Afghan forces had lost 5 per cent of territory this year.
In terms of its own territory, Islamic State has been largely confined to a handful of districts in Afghanistan's Nangarhar province, which borders Pakistan, where IS militants - mostly defectors from the Taliban - are blamed for raiding villages and government outposts.
Still, worries that Islamic State might be expanding its operational reach heightened this week when the group took credit for an attack on a Pakistani hospital that killed at least 74 people in the southwestern city of Quetta. A Pakistani Taliban faction also claimed responsibility.
A few weeks earlier Islamic State claimed an attack on a rally in Kabul that killed more than 80 people.
Khan has been reported dead before. But a claim by Afghan intelligence agents last year that he had been killed was never confirmed.
On Friday, however, Afghan Ambassador Omar Zakhilwal told Reuters he had seen confirmation from Afghan security forces.
"I can confirm that ISIS Khurasan (Afghanistan and Pakistan) leader Hafiz Saeed Khan along with his senior commanders and fighters died in a US drone strike on July 26 in Kot district of Afghanistan's Nangharhar province," he said.
Pentagon spokesman Gordon Trowbridge confirmed Khan's death, saying the air strike took place during joint operations by US and Afghan special operations forces against IS in the southern part of Nangarhar province.