Uncle took property on the basis of fake Will what action can we take

Hello Sir/Madam Advice please us My 4 mama's (Mother ke Brothers) make a fake will after his fathers death and make fool us from last 1992, We know right now open all game from my cousin file case in Hon'ble civil court declare will forge fake will after my grandfather death and taken succession certificate transfer all huge valuable property in his name and sale on big amount taken all huge money from banks how i file first investigate ragistered aganist them or strongly file case 420 how freez acounts of them