hereditary land resold to another party illegally

My hereditary lands were left unattended by my father and so the revenue records were illegally altered. Consequently these illegal intruders using these revenue records created documentation in the registeration department. The total extent sums upto 100 acres. Due to my financial crisis I took up only 5 acres of the total extent and probed into it, and found that the party who sold to us, again sold to another party. I filed a complaint and filed an FIR. But now he has gone to civil suit and claimed that since the case is in legal court, the police cannot enquire him. Kindly advice me in this regard.