Kid Cassidy lucky to survive, says trainer Henderson
Jockey Tony McCoy with Kid Cassidy after his withdrawal at Newbury
Trainer Nicky Henderson thinks Kid Cassidy was "extremely lucky" to have escaped death as two other horses died at Newbury on Saturday.
An investigation has been launched after Fenix Two and Marching Song died in the paddock - while Kid Cassidy was withdrawn after stumbling.
The horses' trainers have suggested they may have had an electric shock.
"Kid Cassidy was extremely lucky as he definitely got the effect," his trainer Henderson told BBC Radio 5 live.
"It was something that none of us have ever seen before and we hope never to see again.
"Kid Cassidy was just walking round and went over on to the grass and knuckled over for a second.
"It does appear it was to do with electricity and underground cables and obviously nobody knew it was there."
On Saturday, a racecourse spokeswoman confirmed a cable, thought to be dormant, had been found under the paddock although she added: "We cannot confirm if that definitely was the reason for the incident."
On Sunday, Stuart Hogarth, operations director for Southern Electric Power Distribution, revealed: "A section of electricity cable has been removed from the paddock area for further detailed inspection.
"Our initial on-site investigations last night confirm there was no danger to the public."
Horses are far more sensitive to electricity than humans, and wet ground conditions may have contributed to the fatal accident.
Henderson added on BBC Radio 5 live: "It was one of the most traumatic five minutes I think one can ever go through.
"This game that we're in is all about horses and everybody loves horses.
"I think they suffered little. There was a brief moment when they staggered around and then they were on the ground and they died.
"One realised shortly afterwards what had happened to Kid Cassidy and he was probably lucky enough to get back on the rubber walkway and he actually had a different type of shoes on to the other horses. It was horrific."
Marching Song's trainer Andy Turnell said one of his team felt an electric shock was to blame.
"My head travelling lad, Colin, held the horse's head and said he felt some form of electricity through it," he told 5 live's Sportsweek.
"The horse suffered slightly but he was dead within 30 seconds. It was very quick.
"We're a very small yard and he was one of our best horses, so it's very disappointing but racing has its ups and downs and that's life.
"I suppose you've got to be pleased more horses weren't stricken. It was just a tragic accident."
British Horseracing Authority chief executive Nic Coward echoed Turnell's sentiments, saying: "This was a tragic incident and our thoughts are with the connections.
"It is premature to describe in detail what happened because that would be speculation, but fingers are being pointed at some kind of electrical fault. Post-mortems are also being carried out."
Seven horses made it to the start of the race, which was won by Al Ferof, but the remaining six races of the meeting were abandoned.
Newbury racecourse officials are in talks to see whether the rest of Saturday's card can be staged later this week.
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