Following a recent NATO drone strike in Afghanistan which reportedly killed up to 12 civilians including women and children, NATO said on Thursday that it has begun an investigation into the civilian deaths it had originally denied.

“When allegations arose of civilian fatalities as a result of this mission, ISAF initiated an investigation,” NATO spokeswoman Colonel Jane Crichton told Reuters.

Original reports from Afghan officials on the strike, which took place on September 7th, varied between 8 and 12 civilian deaths—numbers which conflicted with NATO’s claim that 10 non-civilians, or “enemy forces,” had been taken out, with no civilian casualties.

“Four women, four children, two drivers, a merchant and three suspected (insurgents) were killed,” and a four-year-old girl was seriously wounded, Kunar governor Shuja ul-Mulkh Jalala told Reuters, echoing the original reports.