If I were you I would walk out of what ever room he was throwing a fit in and wait till he calms down. Then ask him why he is so angry and tell him it's ok that you won't get angry. He obviously is upset and he is acting this way because he doesn't know how to express his feelings. My son had outbusts like this and I went and bought him a punching bag and when he got angry he would go to the garage and hit the bag then when he was tired he would come in and I would ask him if he wanted to talk. If he said no I left it at that. But for him this works when he gets angry at me or his sister.