That is scary, very scary. I agree about having a safe plan. As was said that behavior is unexceptable, you and the child deserve to feel safe. Boundaries are needed when behavior gets unsafe. You decide what you will and will not accept and stick to it. If you decide to contact the therapist (if he has one) then be prepared to make the anger management classes your boundary. Please keep us posted.

Reality is determined not by what scientists or anyone else says or believes but by what the evidence reveals to us.
-- Alan Hale