Two US Quidditch leagues are to change their names in order to "distance" themselves from Harry Potter author JK Rowling, following a trans row.
Quidditch first appeared as a fictional sport, played by wizards on flying broomsticks, in her book series.
The real-life version is a fast-paced contact sport, played by more than 450 teams in over 30 countries.
A spokesman for the author pointed out these Quidditch leagues had not been endorsed by Rowling in the first place.
In a joint statement first reported by The Times, US Quidditch (USQ) and Major League Quidditch (MLQ) said they would now decide on new names for the game.
The newspaper said possible alternative options put forward by USQ include Quickball, Quicker, Quidstrike and Quadraball.
The joint statement from USQ and MLQ said they hoped the name change would help them to "continue to distance themselves from the works of JK Rowling", who they say "has increasingly come under scrutiny for her anti-trans positions in recent years."
"Our sport has developed a reputation as one of the most progressive sports in the world on gender equality and inclusivity, in part thanks to its gender maximum rule, which stipulates that a team may not have more than four players of the same gender on the field at a time," the statement continued.
Their position has been backed by the equivalent British body QuidditchUK, the national governing body for the sport.
A spokesman from The Blair Partnership literary agency told BBC News: "The Quidditch Premier League, US Quidditch and Major League Quidditch have never been endorsed or licensed by JK Rowling."
Rowling has previously voiced concerns about issues such as the impact of allowing trans women into women-only spaces, but denied accusations of transphobia.
What was the trans row about?
Rowling initially sparked controversy in June 2020 for posting tweets which took issue with the phrase "people who menstruate" – she objected to the avoidance of the use of the word "women".
The author was also criticised by some for disputing the idea that male and female sexes do not exist.
"If sex isn't real, there's no same-sex attraction. If sex isn't real, the lived reality of women globally is erased. I know and love trans people, but erasing the concept of sex removes the ability of many to meaningfully discuss their lives," she tweeted.
In a lengthy follow-up blog, she wrote her interest in trans issues stemmed from being a survivor of abuse and having concerns around single-sex spaces.
She has continued to speak out. Last week, Rowling shared a news article about an MP who had branded as "absurdity" the idea of police saying they will record rapes by offenders with male genitalia as being committed by a woman if the attacker "identifies as a female".
War is Peace.
Freedom is Slavery.
Ignorance is Strength.
The Penised Individual Who Raped You Is a Woman.https://t.co/SyxFnnboM1
— J.K. Rowling (@jk_rowling) December 12, 2021
The BBC is not responsible for the content of external sites.View original tweet on Twitter
On Sunday, Rowling shared a message from a follower online apologising to the writer for having previously labelled her transphobic, when she had been "standing up for women".
Rowling's comments were applauded by some but criticised by others, and many high-profile people associated with her have distanced themselves from her comments about trans issues.
It was recently announced Rowling will not appear on a forthcoming Harry Potter reunion.
Last year, Rowling has said she was giving back an award associated with the US Kennedy family, after Kerry Kennedy said views expressed by Rowling recently "diminished the identity" of trans people.
Harry Potter stars Daniel Radcliffe, Rupert Grint and Emma Watson were among those who have distanced themselves from Rowling's comments. Several Quidditch bodies are now following suit.
Matt Bateman, president of QuidditchUK, told The Times: "We cannot continue to call ourselves Quidditch and be associated with JK Rowling while she continues to make damaging and hateful comments against the many transgender athletes, staff and volunteers who call this sporting community home."
What is Quidditch?
Quidditch is a sport invented by Rowling for her book series Harry Potter, and it first appeared in the 1997 novel Harry Potter and the Philosopher's Stone.
Matches are played on a large oval pitch with three ring-shaped goals. Teams are comprised of seven players: three chasers, two beaters, the keeper, and the seeker.
The team with the most points at the end wins, unless one side locates and catches the Golden Snitch which scores them an unassailable game-winning 150 points.
Harry Potter and his fellow wizards and witches played the game, flying on their broomsticks, at their school, Hogwarts, and elsewhere.
The real-life version, which began on the US college scene in 2007, sees players run with brooms between their legs.
Many American schools, such as UC Berkeley, have added Quidditch to their list of team sports. College teams compete in an annual national tournament, which was won last year by the University of Texas.
The sport has since then spread across more than 25 countries and includes multiple international tournaments, including a World Cup.
In the UK, The Quidditch Premier League is played between 10 teams, split between the North and South divisions.
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