how to get illegally occupied property back.

Dear Sir, I have a question about my relatives property. whose land (in city in Gujarat)was occupied illegally by a person who was the watch man of the said land.That person was employed by my relatives as a watch man because they were living far away from their property and they were unable to visit the land due to their business in another city far away. The watch man made some row houses on the land and sold it to people by writing agreement on stamp paper.After knowing this matter my relatives father had lodged case in a court in 1986 against him but he continued selling the land before judgement and at last there were 320 house holds .After all processes in court finally my relative won the case in 2008.And as per court's judgement the legal owner of the all occupied land was my relative.But even after court's judgement people who were living there are denying to vacant the land arguing that they had purchased the land doing selling agreement,they are continually occupier of the property since 30 years and paying light bills and taxes..etc..the documents of the land in government record showing my relatives names as owners.Now what they should do to vacant their land from these 320 house holds as per lawful process? Thank you.