I'm being blackmailed to have with a guy, cuz he has nude pictures of me.?

I'm 16, and a boy somehow got into my ex boyfriend's email, and got some nude pictures of me. He's threatning to send them out at school, print them out and put them on doorsteps in my neighborhood, and send them in emails to my principal and school board so i'll get kicked out of school. I don't know what to do. I'm scared to say anything, cuz technically i could be arrested because im under the age of 18 so my pics are child . I know i made a big mistake, and i possibly just ****** up my life, but please help me! He wants me to have with him, but i refuse to be his . WHAT SHOULD I DO??