Two-time Cheltenham Gold Cup winner Kauto Star has been put down at the age of 15.
The racehorse, who was trained by Paul Nicholls and owned by Clive Smith, had a successful career winning 23 of his 41 races.
The decision was made to put down Kauto Star after he suffered a fracture to the left side of his pelvis after a fall.
"I am devastated," Smith told the Racing Post. "He had been turned out in Laura's paddock, as has been done normally with him at this time for years, and he looks to have jumped something and stumbled. We're not really sure, but he injured himself, and it became obvious it was serious.
"The vets made him comfortable but it became evident that it was serious, and the kindest thing was to euthanise him. It was a horrible moment. He was such a wonderful horse, but he did not suffer."
Among Kauto Star's race highlights was the King George, in which he won five times.