Author JK Rowling leans out of a steam train named "Hogwarts Express" at Kings Cross railway station in London, July 8, 2000, with her fourth book in the popular children's Harry Potter series, "Harry Potter and the Goblet of Fire". (PHOTO / AP)

LONDON - British police said on Thursday they had received a complaint after a transgender broadcaster reported JK Rowling to them over comments the "Harry Potter" author had made on social media.

India Willoughby, who was Britain's first transgender newsreader, has accused Rowling of a "hate crime" over remarks the author posted on X on Monday.

The author (JK Rowling) has become a controversial figure on transgender issues and the definition of what it is to be a woman, leading to fierce criticism from some trans activists but vocal support from some women's rights campaigners

Rowling has rejected the allegation, saying that it was not a crime to hold gender-critical views.

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"I contacted Northumbria Constabulary yesterday ... I have reported JK Rowling to the police for what she said," Willoughby said in an interview with independent news publisher Byline Times which it posted on X late on Wednesday.

"Calling a trans person a man, deliberately knowing that that person is a woman - and I am a woman regardless of what JK Rowling says ... my birth certificate says female, my passport, all my documents, I am legally recognized as a woman, and for JK Rowling to deliberately, and that is the key word, misgender me knowing who I am, is grossly offensive."

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The author has become a controversial figure on transgender issues and the definition of what it is to be a woman, leading to fierce criticism from some trans activists but vocal support from some women's rights campaigners.

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"Some time ago, lawyers advised me that not only did I have a clearly winnable case against India Willoughby for defamation, but that India's obsessive targeting of me over the past few years may meet the legal threshold for harassment," Rowling wrote on X.

Asked about the Willoughby's accusation, Northumbria Police, in Northern England, said in a statement: "On Monday, March 4, we received a complaint about a post on social media. We are currently awaiting to speak to the complainant further."