Recover money

Hello sir/madam, i gave 5 lac to person in feb 2017 . i was looking a lease house but because of larger amount i choose rented house . that guy told me you gave me 5 lac i will give monthly rented amount to you. within year we asked money to that person but he delayed . his check bounced in feb then he again begging that i will give you within days. his wife badly said bad words to my mother qnd told we are not giving money . after his health condition is not well now he was dead in month of august. now his son also attempt to sucide because there is another person asked money. there is lot of guy who are asking money.and his mother told that our relative that they complaint in police station if anyone asking money we will complaint in police station. we have no idea what to do my father is retired person. please help us.