NEW DELHI (AFP) - Indian police on Wednesday (Sept 12) summoned for questioning a bishop accused by a nun of raping her multiple times, following days of protests by other nuns and supporters.

Bishop Franco Mullackal, who has rejected the accusations, has been called for questioning in the southern state of Kerala on Sept 19, the Press Trust of India reported.

The nun first accused Bishop Mullackal in late June of raping her 13 times between 2014 and 2016, but police until now have stopped short of formally questioning him.

But pressure has been building on the authorities to investigate the claims.

Over recent days, five nuns - in a rare show of dissent within the Indian Church - and dozens of supporters have been protesting in Kerala's capital Thiruvananthapuram.

With media interest growing as well, the alleged victim has also approached the Vatican representative in India to press her case.

Her letter, leaked to Indian media, said Bishop Mullackal was "using political and money power to bury the case".

Bishop Mullackal has called the whole scandal a conspiracy by those against the Church, and has won backing from his congregation at the Missionaries of Jesus Church.

Kerala's High Court will be hearing the matter on Thursday, although the bishop was not expected to attend.

A local politician, Mr P.C. George, has meanwhile made waves by calling the nun "a prostitute".

"Twelve times she enjoyed it and the thirteenth time it is rape? Why didn't she complain the first time?" media reports quoted him as saying.

Kerala is home to India's largest Christian population and one of the oldest in the world.

Related Story Four Indian Christian priests accused of rape, blackmail

In July, two priests were arrested for allegedly raping and blackmailing a woman for over 20 years in the state.

Sexual abuse by clergymen and the failure of senior Church officials to take action has been one of the biggest scandals facing the Catholic Church in recent years.

Pope Francis issued a letter on sexual abuse to the Catholics around the world in August, expressing the Church's "shame and repentance".

Christians - overwhelmingly Catholic - are the third-largest religious group in India.

Around 80 per cent of the country's 1.25 billion population is Hindu, followed by a sizeable Muslim minority.