A U.S. air strike in Afghanistan on Monday killed at least four civilians, Afghan officials say.

According to reporting by the New York Times, which cites information from district police chief Abdul Qayum Noorzai, the attack in the Shindand District of Herat Province targeted four people on motorcycles, none of whom were the Taliban fighters that had earlier in the day fired rockets at an Afghan military base and fled on motorcycles.

Afghanistan's President Hamid Karzai issued a statement on Tuesday condemning the attack, stating, “Any military operations by the foreign forces, targeting civilians and residential areas in Afghanistan means that they do not value Afghans’ lives as well as it is a clear violation of bilateral agreements.”

The Times' reporting indicates that two of the civilians were women, while the statement from Karzai indicates one woman and one child were killed by the U.S. airstrike.

The Times cites a statement from coalition forces as saying they are “working hand in hand with Afghan authorities to resolve this as quickly as possible.”

The United Nations warned last month that civilians in Afghanistan were facing a "disturbing upward spiral" of violence.

“The nature of the conflict in Afghanistan is changing in 2014 with an escalation of ground engagements in civilian-populated areas,” stated UN Special Representative for the Secretary-General in Afghanistan and head of UNAMA, Ján Kubiš. “The impact on civilians, including the most vulnerable Afghans, is proving to be devastating.”