Bigamy by a Bihar govt teacher

Background- i am a working woman and my husband is school teacher under Bihar govt. We are married since 2008. It was a pompous one and a lot of dowry was given still from starting they kept torturing me for more and more money. whatever I was earning they were demanding to give it to them too. I have two girl child, one is 3 years old and another is 2 months old and now I can't conceive another child due to some medical reason but my husband and his family need a baby boy. Now I came to know he has married to someone else in a temple by keeping me in dark, on 06/03/2016 and there were no talk of divorce and anything else earlier. In documentary proof I have his second marriage photographs and Priest is ready to come court with supporting documents and photographs. So now my questions are: 1) what steps should I take now? 2) what charges I can press against them? 3) one of his close relative is an MLA, can he influence the police investigation and court judgment? 4) what are the organisation\institution which can help me in this crisis?