Husband threatening killing after separated

Dear sir, we had arrange marriage to My sister , but he is not has good manners doubting and torturing, not willing to go job and not take care family. SO my sister returned back home after he beaten very badly. He is alcoholic and had police cases went to jail some times for fighting with police men also. around a year He is called and torturing my sister and threatening as he will kill my mother and sisters in midnight. My sister having all his phone conversation. she requested for divorcee but he is threating like he will kill family. Kindly suggests ways to file case against him . Is there way to legally restrict he contact direct/phone, if he tried he should arrest for that. Firstly we should restrict him, so that my sister can freely go to job and meet lawyer to procced divorce case. Kindly do needful to get Restraining Order. Thank you very much in advance for your help.