If an attack has ended, fails to continue, or ceases to persist then it has stopped.
Was the attack at Beslan stopped? Was the attack at Mumbai stopped? I don't think so. Hard to claim you have stopped an attack when there are a hundred folks dead from the attack. As I have said before, some of you seem to confuse stopping a terrorist with stopping a terrorist attack. The two are often very different. You don't stop a murder after somebody has been murdered, even though you stop the murderer.