(KCEN) -- Joint operations with Afghanistan's military are suspended indefinitely after four Americans were believed to have been killed by Afghan troops.
A suicide bomb also killed nine foreign workers and three others near the airport in Kabul.
The group claiming responsibility is angry over the anti-Islam video that sparked protests throughout the Muslim world.
Afghanistan has now blocked it on YouTube.
The U.S. says Libyan authorities and the FBI are cooperating, but Libya's running the investigation into U.S. Ambassador Chris Steven's death.
For now, the American embassy in Kabul is closed.
Americans are warned not to travel to Afghanistan or stay away from crowds if they are there.