My father cousin had did illegal occupation on our house allotted by govt to slums.

Hello, this is Baljeet from Punjab. i live in a house allotted by govt. approx. 60 years ago to slums(as we was). this house was allotted to my father and up to now registered on his name in municipal corporation records.None else has his/her name on the property records. My father let his brother to live in the 2 rooms in which Mr. cousin is now residing with his family. He has never paid a penny for the property's maintenance nor had shared any expenses such as painting, repair work, electrical re-installation etc. although we had paid house rent, water bills,sewer bills and all. we have all slips of that on my father's name. we tried many times but only thing that happen is big quarrel. His entire family starts the same & they all claim that they have their right in the said part of the property.He many times says "I'm the owner by Adverse Possession" Since the property is old he wants to stay there for life time. My father and now me paying the property tax for many years. As I said earlier, Mr.cousin never spent a penny & continues to live for free. What legal actions can i opt in this matter? I wish to make him to vacate my premises ASAP. Please help me find a way. Thanks in advance.