The British dressage star Charlotte Dujardin will not compete in the OS in Paris. On Instagram, the three-time Olympic champion announces that she is withdrawing.
The reason is a four-year-old video that has leaked, showing Dujardin making a "misjudgment" during a training session.
It is not clear exactly what the video shows.
"What happened was completely out of character and does not reflect how I train my horses or train my students, but there is no excuse," writes Dujardin in an Instagram post.
She continues:
"I am deeply ashamed and should have been a better example at that moment."
The International Equestrian Federation (Fei) is investigating the incident and announced on Tuesday evening that Dujardin is temporarily suspended from all events.
"Fei condemns all behavior that is contrary to the welfare of horses and has rules in place to address such behavior," says the federation in a statement.