I hesitated posting this because it is so sick. How do you "not" stop someone doing this? I'm sorry but I know enough martial arts, not an expert you understand, that I would have stopped him. A very hard blow to the throat will stop it when he no longer can breath. How evil can anyone be to do something like this. This is an example of the kind of animals that are loose on our streets. If anyone wants to know why I carry everywhere and eneryday it is because of monsters like this. You never know when you may come face to face with them.