A 911 call cited by CNN reveals the fear Shane Tamura's mother expressed about the safety of her son as well as herself

Crazed gunman Shane Tamura, who shot dead four people at a Midtown Manhattan office building before turning the gun on himself last Monday, suffered from a sports-related concussion and multiple alarming mental health episodes that led his mother to call 911 on him, according to new details released by authorities.

Police say Shane Tamura, the man who shot four people to death before ending his life on Monday, suffered from a sports-related concussion,