"Afghan President Hamid Karzai in strongest terms condemned killing of 16 civilians by a U.S. troop in Kandahar province describing it as 'intentional killing of human'," the statement said.

"The Afghan government had in the past strongly condemned civilian casualties that caused during the military operations by international forces that were called war on terrorism. But when a U.S. soldier intentionally kills innocent people, it could be described as an act of terror, which cannot be forgiven," Karzai said in the statement.