A Father Denied and Abandoned his own son

Hello, Good day! My name is Kim and I am 21 years of age. I have a son which is running 9 months old, during pregnancy until I gave birth the father of my son is financially supported me. After I gave birth, he just abadoned us, no more contact at all. He even changed his phone number and I tried to reach him through their home telephone number still his parents hid their son for him not to face his responsibility. Now he is married, he had an arranged marriage held last November 2013 without informing me, I just knew it when I'd opened one of his social media account. After a month I gave birth I tried to search his social accounts but it doesn't exist, then I saw the account of his wife. I sent a message to her to remind his husband about what he promised to me before they got married that he will support our son until he finish his studies then few days later I got a reply from his wife and she's telling me that his husband is not cruel to abandoned his child, and a simple DNA TEST can prove that the said child is not his son, I was totally mad for what she said to me. My ex boyfriend and I, both knew that this child is our baby. Now, my question is can I file a case against the father of my son? And is it possible to file a case while he is currently living now in INDIA? If possible, what case should I have to file against him? I hope somebody can give me an advise to this issue hence I really don't know what am I going to do, what is the first step should I make. Please help me