Land grabbing using forged documents

I have purchased a plot of area 2400sft in mangadu village during 1983. Original document is still with me. patta not received. During 2012, a forged person, using my name, submitted a duplicate and forgery voter ID in my name, address etc and sold the property to some other person. Again and again it was sold to 3 persons and finally document deposited in a bank. All these 4 transactions were made within a year 2012. The land is still vacant. I made a complaint in police commissioner office, CCB land grabbing cell and after preliminary investigation, they filed FIR on 11.8.18 against 4 persons. till date they have not arrested anybody. By seeing itself, anybody can confirm that the voter ID used is forgery. Kindly advise me, is there any way to cancel the forgery document and get back my property? Thanking you.