U.S. officials have said the deadly attack on a hospital in Afghanistan was a mistake. But was it also a violation of the limited authority under which American forces are operating in Afghanistan?

The U.S. combat mission ended nearly a year ago. Troops are permitted to use force there only under certain circumstances.

Officials decline to fully discuss the circumstances of the attack in Kunduz that killed 22 civilians. But the top U.S. commander in Afghanistan, Gen. John F. Campbell, said Tuesday that he is requiring every U.S. service member in Afghanistan to be retrained on the circumstances in which U.S. firepower can be used. He said he was doing this to prevent any future incidences like the flawed Kunduz attack.

Campbell did not elaborate.