Washington - US forces have killed the leader of the Islamic State group's Afghanistan branch in a raid in the northeastern province of Kunar, the Pentagon said Friday.

"US forces killed Abu Sayed, the emir of Islamic State of Iraq and Syria - Khorasan Province (ISIS-K) - in a strike on the group's headquarters in Kunar Province, Afghanistan, July 11," Pentagon spokeswoman Dana White said in a statement.

"The raid also killed other ISIS-K members and will significantly disrupt the terror group's plans to expand its presence in Afghanistan."

Meanwhile, at least eight Afghan civilians including women and children were wounded in an air strike in a restive southern province, doctors said Friday, as ordinary people continue to pay a disproportionate price in the ongoing conflict.

The strike occurred late Thursday in volatile Sajawal Kala near Tarin Kot, the capital of Uruzgan, a poppy-growing province where the Taliban have a heavy presence.

"At least eight people, all civilians, were wounded" in the strike and brought to a government hospital in Tarin Kot, said Zia-ul-Rahman, a doctor in the hospital.

"Among the victims were five women, two children and a young man," he told AFP. A doctor in the village where the incident took place, Ehsanullah Ehsan, confirmed the incident to AFP, saying it happened late Thursday.

Rahman blamed the strike on "foreign forces". There was no immediate statement from either the US or NATO on the incident.

Civilian casualties caused by NATO forces have been one of the most contentious issues in the 15-year campaign against the insurgents, prompting strong public and government criticism.

In February this year, a US airstrike in volatile Sangin of Helmand province killed at least 18 civilians, mostly women and children.

In November last year, 32 Afghan civilians were killed in a US airstrike in volatile northeastern province of Kunduz.

While in October 2015, a US air strike during fighting hit a hospital operated by Medecins Sans Frontieres, killing 42 people and sparking international outrage.