The United Nations Assistance Mission in Afghanistan called on all warring parties to uphold their obligations to protect civilians and obey international humanitarian law. (Max Bearak/The Washington Post)

The United Nations mission in Afghanistan expressed concern Tuesday over a surge of civilian casualties from airstrikes conducted by Afghan and U.S.-led forces while battling insurgents.

In the latest reports of civilian deaths from such incidents, more than 25 villagers were killed Saturday in two separate strikes in Kapisa province northeast of Kabul and in Wardak province southwest of the capital, several lawmakers and residents from the two regions said. They said women and children were among the victims.

Afghan Defense Ministry officials said they are looking into the allegations, which followed reports days earlier of noncombatant deaths in eastern Laghman and Nangahar provinces.

The United Nations Assistance Mission in Afghanistan (UNAMA) cited the incident in Kapisa province in a statement.

“UNAMA received multiple, credible allegations that on 22 September, aerial ordnance impacted the home of a teacher in the Budrab area of Tagab district, Kapisa province, killing nine civilians, including four children and three women, with several others injured,” the U.N. mission said.

“All the victims from the attack were from the same family, including grandparents and children aged between two and twelve. Five of the six other family members who were injured when their home was destroyed were women and young children,” it added.

The incident took place during operations conducted by pro-government forces against Taliban insurgents in the area, UNAMA said.

It was not immediately clear whether the strike was carried out by international military forces or by the Afghan air force, it added. The U.N. mission expressed concern about “the rising number of civilian casualties from airstrikes this year in Afghanistan.”

Debra Richardson, a spokeswoman for U.S. forces in Afghanistan, said the coalition is “reviewing all operational” information about the strikes. She said the Afghan government is also investigating.

In the first six months of the year, UNAMA said, it documented 353 civilian casualties, including 149 deaths, from airstrikes, a 52 percent increase from the same period in 2017.

“It is of particular concern that women and children made up more than half of all aerial attack civilian casualties,” the mission said.

Several thousand Afghan civilians have been killed each year in fighting since the Taliban was driven from power in late 2001, the United Nations and other agencies have reported.

Annual U.N. estimates in recent years have shown that most of the casualties were caused by insurgent attacks. Last year, for example, more than 10,000 Afghan civilians were killed or wounded in the country’s war, nearly two-thirds of them at the hands of insurgents such as the Taliban and Islamic State, UNAMA reported.

In its latest report, the United Nations mission said 52 percent of all civilian casualties from aerial attacks were attributable to the Afghan air force, 45 percent to international military forces and the remaining 3 percent to “unidentified Pro-Government Forces.”

About 7 percent of all civilian casualties in the Afghan conflict in the first half of 2018 resulted from air operations, it said.

UNAMA called on all warring parties to uphold their obligations to protect civilians and obey international humanitarian law. It also urged all parties to “ensure independent, impartial, transparent and effective investigations” into incidents resulting in civilian casualties.