Tenants creating problem and denying to renew the agreement

My father purchased and rented out his property in the year 2000 to an NGO operated by women for 3 years.The rent is Rs.3000 per month.The agreement expired in the year 2003.After that both parties didn't renewed the agreement.After my father's death in the year 2009, I became the only legal heir of the said property.Since then, the tenants are refusing to renew the agreement after my repeated requests, refusing to vacate the property, refusing to increase the rent as per market rate, objecting to sale the property.Kindly suggest what to do.