Washington (CNN) As the Biden administration grapples with the challenge of carrying out counterterrorism missions in Afghanistan without US boots on the ground, CNN has learned new details about last Sunday's drone strike on suspected ISIS-K fighters in Kabul that some officials say provide insight into the obstacles ahead for military and intelligence officials tasked with fulfilling President Joe Biden's promise to make the terror group "pay" for its deadly suicide attack in Kabul.

The US relied in part on overhead surveillance imagery to target the suspected ISIS-K fighters, according to two US officials.

The imagery showed the suspected ISIS-K fighters loading explosives into the trunk of a car, the officials told CNN. Intelligence assets tracked the vehicle for an extended period of time and saw it stop at multiple suspected ISIS-K locations, according to a third official, and by the time of the strike, the Pentagon had amassed enough other evidence to believe that the vehicle was headed for Hamid Karzai International Airport to launch an attack.

But the cost was high. The strike took place in a tight residential alleyway and appears to have killed at least 10 civilians — including children, according to their families, who spoke to CNN in the aftermath and have disputed that any of the slain were affiliated with ISIS-K. The Pentagon has defended the strike but have said it is now under investigation.