Indian authorities have charged a Roman Catholic bishop with repeatedly raping a nun in her rural convent, a case that helped make the sexual abuse of nuns a public issue in the church.

Hari Sankar, a district police chief in the southern state of Kerala, said Bishop Franco Mulakkal had been charged with rape, illegal confinement and intimidation.

The nun who made the accusations, who has not been publicly identified, said she went to the police last year after complaining repeatedly to church authorities. Eventually, a group of fellow nuns launched unprecedented public protests to demand Mulakkal's arrest.

Mulakkal has angrily denied the accusations, calling them "baseless and concocted."

In February, Pope Francis for the first time publicly acknowledged the sexual abuse of nuns by priests and bishops.