Boyfriend blackmailing that he will commit suicide what can I do

Hi , my girlfriend is blackmailed by her ex-boyfriend . he threatens her that he will commit suicide if she wont patch up with him. and also he threatens her that he will send photos of them being together to her parents. She belongs to conservative family and she is very much worried about it. please help by letting me to know what legal action can i take so that her parents wont get to know about this and her identity is protected from exploitation. please help