Harassment from foreign husband

Respected practitioners, My sister got married to an Indian born guy and a foreign national. Its been 8 years of their marriage but since the day they got married he has been torturing her mentally and physically. He is a very cruel guy. Below is the problems she has been facing in the country she used live with him... 1. He used to take the people in his sweet sweet speeches and adciss to do business with him but as soon as he gets money to invest from the people he just take it and run away to another city. 2. Because of his such habit the investing people often call him and tell him to return the money or else they will ruin his family.some of the people even tell that they will kill him. 3. Believe me my sister isn't safe in that country.many times she also had to run with him at midnight with her wet eyes. 4. When she cries n complains to him that what kind of life have u given me and he starts beating her. 5. He often tortures her mentally. 6. Many times he just comes home with the anger for the people calling him for money and my sister just gets afraid of him because he just beat her in anger for no reason. 7. He used to go to casino and he is a big gambler. 8.my sister doesn't have permission of him to go out of the home to buy vegetables and grocery. He doesn't like even if she speak to a shop keeper while buying the stuff. 9. She doesn't have permission to use whatapp and facebook. Everyday he checks her call records. 10. She doesn't have permission to attend any marriage of our relatives residing in that country. 11. My sister can't live the window open of her house because he doesn't like if anyone sees her passing from the window. One day by mistake she kept kitchen's window open just to clean it and she was frying the samosas and her husband came suddenly and he attempted to pull her head to the kadhai she was frying samosas in. Fortunately she managed to save her head that day. 12.They have one 7 yrs old daughter and she is just at home not going to school because many time she was in school and they had to run away for people's notice calls that if u don't return the money today they will kidnap her daughter. She can't go to school even. 9. He used to call and swear to my father when my father advise him to leave his such habits. 10.He even had recorded my sister's necked video secretly and used to blackmail her that if she complaints anything about him to her relatives he will publish it on the internet. Now 2 months ago he called my father that he and my sister have to come to India right today. We all were just wondering how its possible that he is coming to India with her suddenly. And after few days we got to know that he has again looted a Pakistani guy living in his town there. And that Pakistani guy was supposed to kill him that's why he is here in India at our home. Now 15 days ago he has returned to his country alone.as we requested him to keep my sister and their daughter here with us in India untill he sorts this matter out with that Pakistani guy. But now we refused to send my sister there to him and asked him to divorce her. Even my sister has refused to go to him. But he is clearly refusing to divorce her and swearing all of us on the phone since a week. And he even published the necked video of my sister on the net and also sent it on my relatives whatsapp. We contacted our nearest lawyer for this issue but she said as he is not an Indian citizen and living out of India its difficult to catch him through court. But when I phoned one more expereiced lawyer he said we must write a complaint and submit to the DSP officer and he will do the rest. But I am confused that is it really gonna work without a strong back ground? Please advise me what to do m really in a big trouble all of my family member can't even sleep at night. Please advise me I will really really appreciate it.