A U.S. air strike on a village in Eastern Afghanistan killed three civilians—a woman and two children—the Afghan president's office revealed Tuesday.

Local officials say a NATO aircraft fired at a family in the Nadir Shah Kot district of Khost Province, killing three and wounding one man, The New York Times reports.

The attack occurred late Monday night and prompted an immediate condemnation from Afghan President Hamid Karzai, who slammed the attack as a "violation of agreements," Reuters reports.

NATO, which is led by the U.S., released a statement claiming it is investigating the incident.

The loss of life comes amid mounting civilian deaths from U.S. and British covert drone strikes on Afghanistan.

According to a recent report by UN special rapporteur on human rights Ben Emmerson, data for 2013 shows that drone strikes in Afghanistan accounted for 40 percent of civilian deaths by pro-government forces, marking a three-fold increase since 2012. According to the United Nations Assistance Mission in Afghanistan, in 2013 at least 45 civilians died in drone strikes in Afghanistan.

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