Dear Mr Pushkar,
You are having two choices with you:
1) Send them a legal notice saying that they have tress pass your land property and why not they be required to remove their hoardings and bill boards which they have placed on your property with out your permission and after the time limit you yourself remove them all.
2) after giving them the legal notice you file a case under tort for compensation and damages which you have suffered by putting these billboards on your property and allow an injunction against them by ejecting all this nonsense on their expenses only.
In my opinion the second way is mush better for you.
For further legal assistance on nominal charges, you can contact me on below mentioned address and Phone number, Please call after Court hrs to get a suitable appointment date and timing.
Advise, always take assistance from an experienced and well educated Advocate of the field. You can see my credentials on this very site for my appraisal.
for Anand Bali & Associates
Anand Bali, Adv.
(B.Com., M.A., LL.B., M.B.A.)
Supreme Court Of India,
High Courts of Delhi, Chandigarh, UP & UK.
For Civil, Criminal, Property, Recovery, Consumer,
Service, Divorce & Family Dispute matters.
Off:
204-B, Nanda Devi Apartments
Plot-19, Sec-10;
Dwarka,
New Delhi -75
Ph: 09582144748