Up to eight policemen have been killed in Afghanistan as a result of US airstrikes, Reuters reports citing officials. The US has confirmed one airstrike, but insists the assault was in response to a threat.An initial airstrike killed one policeman late Sunday, while a follow-up strike targeting first responders killed at least seven others, said Rahimullah Khan, commander of the reserve Police unit in Uruzgan.

The US military command in Kabul has confirmed its warplanes conducted an airstrike in the area, but said those targeted were “individuals firing on, and posing a threat to” Afghan national security forces.

"We don't have any further information on who those individuals might have been or why they were attacking ANDSF [Afghan national defense and security forces]," US military spokesman Brigadier General Charles Cleveland said in a statement.

"US, coalition, and Afghan forces have the right to self defense and in this case were responding to an immediate threat," Cleveland added.

Afghan officials said they are investigating the attack and communicating with the US-led coalition.