Parents skeptical about background - family of boyfriend- not agreeing

I am in relationship with a guy for past 1.5 years. We both love and respect each other a lot. He's very serious about me. I have a family of 4: my mom, dad, younger bro and me. Past 6 months back I told y mom about my guy. Initially she was Ok and was interested in knowing a lot about him and his family. We both are from different states and we do not have any common link between our families. My family is very conservative. They are of the view that my marriage should be done from the people who belong to our native state and some common connection like a trustworthy mediator should be there. They told me its not possible for me to get married to my guy (as they aren't aware of the authenticity of his and his family's whereabouts specifically coz of social stigma). Now they have seen two guys for me. My mom came to me and asked me to tell which one out of those two would I like to choose my future hubby. I told her that I would like to marry the guy of my choice. My father threatened me of worst consequences ( like killing my Boy friend or spoiling his career, my house arrest, loss of my freedom-no studies, no job etc.). I can't risk his life for my happiness and can't marry any other guy. Me and my guy don't want to go against the wishes of our families but things are not working. We can't imagine our lives without each other. What to do:confused:...please help. We both want to have an love cum arranged marriage.

well thanks for writing us,
The first question that comes to my mind after reading your post is what made your Mom ready initially for ur relationship with your guy, hadn't she knew where he belonged too earlier when she was Ok with it, and if she was ok then, than the reasonibg if his family background and whereabouts doesn't hold true.
What is ua family background, do you belong to the family wgo is involved in politics???? the reason behind this is very simple that is ua dad's threatening replies to u????
I strongly believe there his some other reason behind this rejection......

When I asked my Mom about the same she said that this was one of her strategies to know what's going on in my mind. So that she can let my dad know about it. My family is not politically involved anywhere. My father is in a pvt job but he is very specific about relationship issue as he thinks it directly affects his social respect and other so-called things. Actually the thing is that I come from a traditional Hindu family where marriages are arranged by parents and children are not supposed to interfere. All the marriages in my family are done within our native state but mine is out of state case so my parents are not agreeing. Actually the main reason that I am able to conclude is that we both worked in same office and my bf is still working there. I have left that office now. My father has threatened me if I keep on repeating the same issue ( marriage with my guy) he will go to office and let everyone know of our relationship. My bf don't want such a scene as it could affect his career and personal reputation adversely. My bf's family have no issues with our relationship. They are willing but they want my family to initiate the whole process. I don't know wat to do in such a situation. Please help me out guys.