Girl friend is under house arrest by her parents

This is satheesh. My girl friend name is REMOVED. We are in love for last 4.5 years. She got one alliance 10 days back. Her parents interested in the alliance. so try to marry her with him. so we reveal our love matter to their parents through phone. We are working in bangalore. From the instance we tell our about our love to their parents. They started opposing. They not even listen to our words. We said "we love each other. We want support from both the parents. So please marriage us.".They wouldn't listen to us. I am working in MNC earning 25K per month. she s also working in one MNC earning 20k. We said to their parents we will as long as for your approval. Then they said "Ok. you please to home this weekend we will talk about this." so she went to home. But once she reach home, they won't accept our proposal and do some emotional black mails. They take her mobile ,SIM, internet access everything and also House arrest her. They call to her company and said to her manager "she is going to marry,so she is going to resign". I am not able to contact her. They wont let her to speak to any of her friends also. I am feel like dying. I am not able to do or concentrate on anything. I speak to her dad but he not even listen to us. He said "This wont work out. Because you both are same age, you both from different caste. And what the society will think about me" My family is upper middle class family. I am able to support her financial. Now I am ok to do anything for her. If she said "Ok we will run away means , am also ready to run away". But i am unable to contact her. I don't know what to do next. Please help me. I beg you, I cannot live with her. I cannot leave her. Please help me in