A US drone strike targeting a suicide bomber ended up killing 10 members of one family, including six children, surviving relatives have told the BBC.
The 10 were killed when a car parked at their home was struck by an explosion on Sunday.
The US military said a vehicle carrying at least one person associated with the Afghan branch of the Islamic State group was targeted.
It said people nearby may have been hit in the aftermath of the strike.
Some of those killed had previously worked for international organisations and held visas allowing them entry to the US, the BBC has been told.
The youngest child to be killed was two-year-old Sumaya, and the oldest child was 12-year-old Farzad.
Ramin Yousufi, a relative of the victims, said: “It’s wrong, it’s a brutal attack, and it’s happened based on wrong information.”
Another relative, Emal Ahmadi, told the BBC that it was his two-year-old daughter who was killed in the strike.
Mr Ahmadi said he and others in the family had applied for evacuation to the US, and had been waiting for a phone call telling them to go to the airport.
That included one of his relatives, Nasser, who was killed in the strike and had previously worked as a translator with US forces.
The US, he added, had made “a mistake, it was a big mistake”.
US Central Command has said they are investigating reports of the incident, but are unclear how the 10 died.
image captionThe aftermath of the drone strike in the Afghan capital, Kabul
In a statement, it said there had been a number of “substantial and powerful subsequent explosions” following the drone strike.
It said the explosions suggested there had been “a large amount of explosive material inside, that may have caused additional casualties”.
Central Command had previously said the strike was successful at “eliminating an imminent” threat to Kabul’s Hamad Karzai International airport from IS-K (Islamic State Khorasan Province), IS’s Afghan affiliate.
image captionRelatives said no one had any links to the local Islamic State group
The US has been on high alert since a suicide bomber killed more than 100 civilians and 13 US troops outside the airport last Thursday. IS-K claimed responsibility.
Many of those killed had been hoping to board one of the evacuation flights leaving the city, which fell to the Taliban on 15 August.
The US had repeatedly warned of an increase in attacks as 31 August – the date set for the Americans’ withdrawal from Afghanistan – drew closer.
On Monday, a US anti-missile system intercepted rockets flying over the capital towards the airport, an official told Reuters news agency.
Video and pictures carried by local news outlets showed smoke wafting across the rooftops of Kabul, and what appeared to be a burning car on a street.