How to recover money given to relatives

One of our relative has taken 5 lakh rupees on the basis of selling his portion of the property which we did not buy as the banks will not give loans for the unapproved plots. We requested them to give back our 5 lakhs. They asked for 1 month time which we gave and promised that by 20 th evening they will return back our 5 lakhs. Later on we got a call from the Sub inspector of police saying that a case was filed against us for threatening them to give the money. They have accepted that they have taken 5 lakh money form us and they were asking for 5 months time to repay the money. They are simply lying and dragging the case. We are paying the interest for the 5 lakh. Please let us know what can be done.