Someone is blackmailing, defaming and has published a defamatory

I am a woman police Inspector in Meghalaya police. My name is Shahana Mukherjee. I enlisted as a direct sub-inspector in 1991. I am still single as my own mother and sister tortured me from childhood. They then threw me out of the house 10 years ago. I have been living alone since in a govt. quarter. on the 23rd of May an article appeared in the local daily defaming me. A man calling himself Sabyasachi Mukherjee has gone to the CM and Governor posing as my legal husband and also says he has a daughter named Rupali from me and knows me fro when I was one year old n this matter is known to my mother n sisters. This man has been hired by my mother n sis. On enquiry by my SP it has been found that there is no such person by the name Sabyasachi. I sent a legal notice to the editor of newspaper S.S.Jha n he replied that he does not know the person n also he has left Shillong. Pl advise me. I want a civil n criminal case also. Should I file an FIR against the editor S.S.Jha or against the impostor?