At least 11 Afghan civilians were killed and 16 wounded on Wednesday when a NATO helicopter attacked a house where Taliban insurgents had taken shelter in Logar province, east of the capital, Kabul, the local governor said.

There was no immediate confirmation that NATO or U.S. aircraft were involved, but a spokesman for Resolute Support, the NATO-led mission in Kabul, said in an emailed statement it was aware of the reports and was looking into them.

"We are still not clear on what happened there, we are looking into it," U.S. military spokesman John Ross said.

Logar Governor Halim Fedaee said the incident occurred in Dashte Bari district near the provincial capital Pul-e Alam.

"The Taliban took position in a civilian house and fired a rocket at a NATO helicopter," the governor said. "The house owner begged the Taliban to leave, but they didn't. The helicopter took a turn, came and hit this house that caused these deaths."

The incident, a day after reports that an Afghan air strike killed at least 13 civilians in the western province of Herat, underlines the risk that a recent increase in air raids by U.S. and Afghan forces will increase civilian casualties.

The U.S. are the only foreign military force still carrying out air strikes in Afghanistan.

The number of U.S. and Afghan air strikes against Taliban and Daesh terrorists is rising fast.

With the Afghan forces stretched thin and demoralized, the military is often relying on air strikes as the last resort to drive the terrorists back.

According to the UN, the number of civilian casualties from US and Afghan air strikes in the first six months of 2017 increased by 43 per cent compared to the same period in 2016, with 95 killed and 137 wounded.

Civilian casualties caused by U.S. air strikes have long been a source of friction in Afghanistan, and the risk of further casualties may increase if the U.S. steps up operations as part of President Donald Trump's new strategy for Afghanistan .

Earlier, Resolute Support denied a Taliban statement that a U.S. helicopter had been shot down in Logar province. It said a helicopter had made a precautionary landing for a maintenance issue.