Civilians were accidentally killed during a NATO airstrike in Afghanistan, the organization's International Security Assistance Force said in a statement Saturday.

The statement did not specify how many civilians were killed and wounded in the Friday operation in Helmand province, which aimed to kill or capture a senior Taliban commander.

The airstrike hit two vehicles "believed to be carrying the Taliban leader and his associates based on intelligence reporting," the statement said.

The force is investigating.

Earlier this month tensions flared over the issue of civilian casualties caused by the NATO forces fighting in Afghanistan after nine Afghan boys died in a helicopter attack targeting Taliban insurgents.