One gunda mafia in my town removed stairs

My father's shop is on first floor. It has 3 stairs to reach the shop. One stair is clearly on outside and it is kind of obstacle for back side land. One person has bought back side land and gave us warning that please remove the outside stairs. My father protested and in land papers it is written that one stairs should be present. But it is not written in papers that which stairs should be taken accountable. So my father has some contacts and contacted one of his nagarpalika friend. My father's friend had brought temporary stay. That gunda mafia came to my fathers shop and asked to remove the stairs. My father shown him shop papers. Now same gunda mafia removed same outside stairs midnight. There are 2-3 people affected due to same action. None is ready to take action. My father is also not ready to take action as he switched his business and not using same shop. The problem is it will bring down the evaluation of shop. Should i fight or should i just leave it? If i have to fight ,how can i move legally