Charles Dharapak/AP

Obama says those accountable in Afghan killings will face 'full force of the law'

President calls the killings 'unacceptable,' 'outrageous.'

President Obama called the weekend killings of Afghan civilians "unacceptable" and "outrageous" and said that anyone involved will be held accountable "with the full force of the law."

Speaking to reporters in the Rose Garden on Tuesday, Obama said he was "heartbroken over the loss of innocent life." An American soldier is accused of leaving his base in a remote part of southern Afghanistan on Sunday and going door to door, shooting Afghan civilians. At least 16 died, including nine children.

"The United States takes this as seriously as if it were our own citizens and our own children who were murdered," he said.

The president said he has directed the Pentagon to spare no effort in conducting a full investigation. "I can assure the American people and the Afghan people that we will follow the facts wherever they lead us," he said. "And we will make sure that anybody who was involved is held fully accountable with the full force of the law."

So far one soldier is in custody while the Pentagon investigates.