Hard-line Christian groups anxious that mild-mannered Harry Potter is an occult conspiracy are unlikely to be reassured by the revelation that one of its key characters is gay – but equalities campaigners wish that it had been made explicit in the books.

Multi-million pound best-selling Potter author JK Rowling revealed that Hogwarts school headmaster Albus Dumbledore is gay to a packed house in New York’s Carnegie Hall this weekend, as part of her American book tour.

She took questions from the audience and was asked, following endless speculation on fan sites, whether Dumbledore had found “true love” before he died in the sixth book in the series.

“Dumbledore is gay,” Rowling replied. She added that he was smitten with rival Gellert Grindelwald, who he beat in a battle between good and evil wizards long ago.

The surprised New York audience applauded the news.

“I would have told you earlier if I knew it would make you so happy,” Rowling laughed. “Falling in love can blind us to an extent… Dumbledore was horribly, terribly let down” and his love for Grindelwald was his “great tragedy”.

The religious right, which has already accused the books of promoting witchcraft among children – an idea that Rowling, who has had links with the Episcopal Church and is now a member of the Church of Scotland, has described as “preposterous” – is likely to be furious at the news.

Rowling also broke her previous silence on the much-debated question as to whether religious themes permeate her books, confirming that they echoed her personal struggle with faith.

She was open about the Christian allegories in her latest book. “To me, the religious parallels have always been obvious,” Rowling said. “But I never wanted to talk too openly about it because I thought it might show people who just wanted the story where we were going.”

At the end of her latest and final installment in the series, Harry Potter and Deathly Hallows, there are specific references to Christianity and themes of life beyond death and resurrection.

Rowling’s confirmation of the existence of a positive gay character in her books was welcomed by equalities and lesbian and gay rights campaigners today, including OutRage and Green activist Peter Tatchell.

However they say they wish Dumbledore’s sexuality had been made more explicit in the books. The matter has arisen in relation to scripting issues with the highly successful spin-off films.

Also on Ekklesia: Reading Harry Potter too religiously (Simon Barrow); Finding faith in the deathly hallows; Pope finds himself pitched against Harry Potter; Pullman says CS Lewis tales are insufficiently Christian.