Received notice based on fake Sale Agreement(made on 2010) of property.

- Ancestor property which is registered to Mr A & Mrs B. - Below points are mentioned in the received notice: 1. Sale agreement of the said property is done with opponent Party(Who has sent the Court Notice) on 2010 with Mrs B. 2. Execution of the said agreement could not be processed due to sudden demise of Mrs B (Oct 2011) 3. Mr. C & Mrs D (Mrs D Only Daughter of Mr A & Mrs B) has inherited the said property 4. After demise of Mr C (Aug 2012) )& Mrs D (May 2012), it is inherited to their daughters D1 & D2. 5. D1 & D2 are trying to sell the Property by publishing an advertisement on newspaper by knowing the fact that Agreeement is in place. 6. Names of D1 & D2 are registered on Survey Maintenance Record of that Property. 7. Agreed selling price of said property was 40 Lakh Out of which 8% cash was given at the time of Agreement(2010) by Opponent. Now opponent wants the Property to be sold to him based on 2010 agreement. As D1 & D2 are aware that there is no such sale agreement done,neither they ever published any sale advertisement in newspaper, makes them very sure that some goons are trying to get the property with fake documents. Below are the queries wrt the above mentioned case. 1. How can we verify that the agreement discussed is not fortefied. 2. How can we know about agreement validity ? 3. Does Court accept the opponent statemnet about paying partial upfront amount in cash? 4. Can we file a case against opponent party for 420 Cheating & Fraud before first hearing? 5. Can we sue the news agency who published the sale advertisement on behalf of D1 and D2 without their knowledge. 6. Opponent might have strong political connection, what all precautions should we taken care of?