A drone strike in Kabul last month killed as many as 10 civilians, including seven children, the US military said on Friday, apologizing for what it called a "tragic mistake".

The Pentagon had said the Aug 29 strike targeted an Islamic State suicide bomber who posed an imminent threat to US-led troops at the airport as they completed the last stages of their withdrawal from Afghanistan.

Even as reports of civilian casualties emerged, the top US general had described the attack as "righteous"...