Procedure to recover amount from known person who is delaying it

I gave a hand loan of Rs 16 lacs to a known person by cash on 08 March 2014. Took original open plot sale deed, promisory note, signed empty bond papers (3), 5 empty signed checks as security. Struggling to recover the money. He says every time he will return in a week/ 10 days but not fulfilling his word. Pls suggest how I can recover it legally.