Video footage has emerged of Charlotte Dujardin whipping a horse "like an elephant in a circus” which has led to her withdrawal from the Paris Olympics.
The Team GB dressage rider, who has won six medals including three golds in a glittering OIympics career, has been suspended over the incident that occurred four years ago.
The video was sent to the International Federation for Equestrian Sports (FEI) on 22 July - two days before the start of the Olympic Games.
talkSPORT has obtained the footage, which shows Dujardin walking alongside the horse being ridden by a teenage girl, and striking its legs repeatedly with a whip.
The FEI, the British Equestrian Federation and British Dressage are all investigating the matter, and Dujardin has been forced to withdraw from the Games in Paris.
The FEI said it had received a video 'depicting Ms Dujardin engaging in conduct contrary to the principles of horse welfare'.
The suspension bars Dujardin from any competitions or events under the FEI's jurisdiction and those run by by a national federation.
The governing body added: "This video was submitted to the FEI by a lawyer representing an undisclosed complainant.
"According to the information received, the footage was allegedly taken several years ago during a training session conducted by Ms Dujardin at a private stable.
"Upon receiving the video, the FEI promptly initiated an investigation. As part of this investigation Ms Dujardin, British Equestrian and British Dressage were informed of the allegations.
"Subsequently, Ms Dujardin confirmed that she is the individual depicted in the video and acknowledged that her conduct was inappropriate.
"On 23 July, Charlotte Dujardin requested to be provisionally suspended pending the outcome of the investigations and voluntarily withdrew from the Paris 2024 Olympic Games."
Dujardin’s statement read: "A video has emerged from four years ago which shows me making an error of judgement during a coaching session. Understandably, the International Federation for Equestrian Sports (FEI) is investigating and I have made the decision to withdraw from all competition - including the Paris Olympics - while this process takes place.
"What happened was completely out of character and does not reflect how I train my horses or coach my pupils, however, there is no excuse. I am deeply ashamed and should have set a better example in that moment.
"I am sincerely sorry for my actions and devastated that I have let everyone down, including Team GB, fans and sponsors.
"I will cooperate fully with the FEI, British Equestrian Federation and British Dressage during their investigations, and will not be commenting further until the process is complete."
FEI president Ingmar De Vos said: "We are deeply disappointed with this case, especially as we approach the Olympic Games in Paris.
"However, it is our responsibility and crucial that we address any instances of abuse, as equine welfare cannot be compromised.
"Charlotte has expressed genuine remorse for her actions, and we recognise and appreciate her willingness to take responsibility.
"Despite the unfortunate timing, we believe this action reaffirms the FEI's commitment to welfare as the guardians of our equine partners and the integrity of our sport."
Stephan Wensing, a lawyer for the person who shared the video, told Good Morning Britain his client had sponsored a lesson for the teenage rider on the horse.
"My client used to be a sponsor, and she was in the UK, and she sponsored a lesson for Charlotte to a student. It was a young girl of 19 years old riding her horse, and she got a lesson from Charlotte Dujardin in the UK," he said.
"Charlotte Dujardin was in the middle of the arena. She said to the student, 'your horse must lift up the legs more in the canter'.
"She took the long whip and she was beating the horse more than 24 times in one minute and really hard, really harsh, really tough. It was like an elephant in the circus.
"This is not just one incident. My client has visited Charlotte Dujardin's stable more times and she has seen it happen more times."
A British Olympic Association spokesperson said: "The British Olympic Association can confirm the withdrawal of Charlotte Dujardin from the Paris 2024 Olympic Games, and we acknowledge the seriousness with which she is taking this matter."
Dujardin has also been dropped as an ambassador for horse welfare charity Brooke, an organisation dedicated to improving the lives of working horses, donkeys and mules in developing countries.
The 39-year-old could have become Britain's most decorated female Olympian in Paris.
A medal of any colour would have taken her clear of cyclist Dame Laura Kenny, with whom she is currently tied on six medals.
She was due to compete in both the individual dressage and team event, alongside Carl Hester and world champion Lottie Fry. She is is likely be replaced in the team by Becky Moody.
Just a year after turning pro, Dujardin won double gold at London 2012, winning the team dressage and individual dressage with Valegro.
Dujardin and Valegro successfully defended the individual title at Rio de Janeiro in 2016 and also won the silver medal in the team event.
And at the Tokyo Games in 2021 Dujardin added two bronzes to her impressive collection, claiming third in the team and individual events with horse Gio.
However, Dujardin will not be competing at Paris 2024, which starts on Wednesday before the official opening ceremony on Friday.
British Equestrian and British Dressage issued a joint statement confirming they have also provisionally suspended Dujardin.
BE chief executive Jim Eyre said: "As the guardians of equestrian sport, we must uphold the highest standards of equine welfare - the horse's wellbeing is paramount.
"The allegations made are serious and the consequences far-reaching but upholding the integrity of our sport remains our priority - we are privileged to enjoy the company of horses; we must never compromise on their wellbeing."
Olympic and equestrian authorities have taken an increasingly strict line against alleged improprieties relating to the treatment of animals.
During the Tokyo Games, a German modern pentathlon coach was thrown out for punching a horse.
The incident sparked a major overhaul of the sport, resulting in the equestrian element being removed completely, and replaced by an obstacle course for the first time in Paris.
Who is Charlotte Dujardin?
Born in Enfield, Dujardin was brought up in Hertfordshire and started riding as a two-year old.
She went on to become the most successful British dressage rider in the history of the sport and the winner of all major titles.
Dujardin holds every world record in dressage and is a multiple World and Olympic champion, as well being Britain's joint-most decorated female Olympian of all-time, along with Dame cyclist Laura Kenny.
Dujardin announced herself to the equestrian world and beyond at the London 2012 Olympics when she won team and individual gold medals on the horse Valegro. The pair went on to win individual gold and team silver four years later in Rio.
On a different horse, Gio, she won two bronze medals at the delayed Tokyo 2020 Games, which took place in 2021.
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