Procedure to claim the land when buyers are missing

Legal heirs have responsibility. 

There are two classes of heirs that are delineated by the Act.

Class I heirs are sons,daughters, widows, mothers, sons of a pre-deceased son, widows of a pre-deceased son, son of a, pre-deceased sons of a predeceased son, and widows of a pre-deceased son of a predeceased son.g responsibility. the legal heirs are 

the legal heirs under Hindu succession Act have rights responsiblities.  find the other legal heirs and then file case if necessary after consulting a lawyer.

Thanks Mr. Ramachary and Mr. Satyanarayana.

We tried various attempts to find her close relatives with no success.

Does a paper notice or sending a legal notice( to the address given in the agreement) would help to make a ccase in the court?

Dear Mr. Satish,  can u please clarify  who is the buyer here,,,,, u are claiming u have paid 3 lakhs towards agrement of sale......further the buyer is dead ?........  If u have paid  Rs.3 lakhs ,  in that case u r the BUYER.......  if u mean  the  SELLER  is  dead  and no legal heirs to execute  SALE DEED on behalf of  the dead SELLER.......... IN  that  case  I suggest  u take possession of  the property.....for time being and  establish yourself as  possession  holder........  rest if some one comes forward  claiming  their rights......then u show them the sale agreement and u r possession.......  if  not  u can take  the matter before court and u can get the same  registered.            If u need further assistance  I am in Bangalore and available on 9845285555.   Warm regards.