An Afghan girl wounded in an airstrike receives treatment at a hospital in Jalalabad, Afghanistan, on Oct. 28. (Parwiz/Reuters)

This year is well on its way to be the deadliest for Afghan civilians since the United Nations mission there began documenting those numbers seven years ago. An incident Thursday is a particularly tragic example of how more and more of those deaths are occurring: at the hands of Afghan government forces and their NATO-led coalition allies.

During clashes with Taliban fighters who are trying to recapture the northern city of Kunduz, an errant coalition airstrike killed dozens of civilians. News agencies have been able to confirm 26 deaths, but at least one local government official estimated the toll will reach 100. The U.S. military said that its forces were defending friendly forces and that “all civilian casualty claims will be investigated.”

At least 2,562 civilians have been killed this year in Afghanistan, according to the United Nations, which has released only numbers pertaining to the period between January and September. Last year's total was 2,681.

Taliban and other antigovernment forces are responsible for 61 percent of that toll, but those numbers are down 12 percent from the same period last year. On the other hand, 623 civilian deaths are attributable to “pro-government” forces this year, up by 42 percent from last year. Many of them were caused by errant airstrikes.

The most notable instance also took place in Kunduz, just over a year ago, when the city had fallen into Taliban control. Acting on faulty intelligence, a U.S. airstrike hit a Doctors Without Borders hospital, killing 42 people. Subsequent reports question whether the Afghan army, which provided the intelligence, in fact wanted the hospital targeted as doctors were thought to have treated Taliban fighters there. Doctors Without Borders called the strike a war crime.

The civilian death toll provided by the United Nations is unlikely to be comprehensive. It is difficult to gather data on killings that happen in Taliban-controlled areas of the country, and more of the country is falling into their hands.

Civilian casualties are a major source of tension between the Afghan government and its NATO allies. With each errant strike, more and more Afghans lose faith in their government, which works hand in hand with its Western allies on intelligence and military operations.

In Kunduz, angry relatives of the victims of Thursday's airstrike tried to parade the bodies of their loved ones through the city in a protest caravan to the provincial governor’s residence. They were stopped by security forces.

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