What legal action to be taken in case of false accusation of rape

One of my friend's father got accused of rape by the woman who was staying with them to nurse her(my friend) grandmother. The woman have one child who was with her and she was living with my friend her father and mother and her siblings and grandmother. The victim alleged my friend's father of rape out of the blue when she demanded money all of a sudden and they denied saying why will we give you 50k just like that so she blackmailed and so my friend called the police but the police took her father and the victim with them and kept over night and then jailed my friend's father. His bail petition got rejected and now my friend is very worried. So what to do?