Removing encroachment from near the NH-8

Before 30 year back a person named Sachina Nand Yadav came from UP in our village Roopangarh Ajmer(305814) Rajasthan and asked for small land near the road (NH-8) to make a temple in our village. In that time, there is no temple near to the our home, so my grand father allowed him for the temple and my grand father not educated so they didn't take any legal agreement for giving the small part of land for creation of temple. After few years creation of temple, my grand father went to outside for work and in that time Sachina Nand create a room and small enchroached 10 feet of land. I have no idea that why my grand father didn't say anything to him. From here everything remained same till Jan 2013. In Feb 2013 son of Sachina Nand named Sunil Yadav constructed one more room. My father said to them to leave the this land but they didn't leave. And they beat my father. After that my father went to the near police station, in police station the inspector said that the encroachment near to the NH-8 and this area comes under the PWD, You have to contact to PWD. And father come back from police station and went to the PWD with full report that claims that the constructed temple and constructed rooms are encroached on our land. But nothing is happened. After the 3 years my grand father expired and increased their encroachment. They want only fight with us and not ready to leave. From present situation it seems that they will never leave our land. If they leave than my family can take it in any other use. Temple is constructed approx 30 feet from the NH-8 and the all encroached land is 1200 square feet including temple. And now we want to destroy the all encroached area including the temple also. It is better for me if any one can help step by step. Thankyou!