The trainer of Grand National runner Hill Sixteen, who suffered a fatal fall at the first fence, has blamed "ignorant" protesters who delayed the race starting for the fall.
Merseyside Police arrested more than 100 people after they attempted to gain entry to the track ahead of the Randox Grand National on Saturday. Dozens of activists climbed fences at Aintree, with at least two affixing themselves to a fence using glue and lock-on devices, climate and animal rights group Animal Rising said.
The protesters breached security fences as the National runners were in the parade ring, causing a delay of around 15 minutes to the feature event, which eventually got under way at 5.29pm. Out of 39 runners, 17 horses finished the race with the Sandy Thomson-trained Hill Sixteen suffering a fatal fall at the first fence, adding to the deaths of Dark Raven earlier in the afternoon and Envoye Special on Thursday.
Hill Sixteen's trainer Thomson said the delay "unsettled" everyone. "It was all caused by these so-called animal lovers who are actually ignorant and have absolutely no idea about the welfare of horses," Thomson said.
Speaking on BBC Radio 4's Today programme, Thomson added: "There were quite a lot of the horses buzzed up."
When asked if he had considered withdrawing Hill Sixteen from the race at that point, the Scottish trainer explained: "When they got down to the start, nobody quite knew what was happening. The starter wanted to get them off as quickly as possible, then the horses were drawn forward then told to get back.
"One of the other things missing was the parade. I think that gives the horses and the jockeys that couple of minutes to gather their thoughts and that didn't help the situation either."
There have been five fatalities from 395 runners in the 10 Grand Nationals raced since safety changes were introduced in 2012.
"Nobody wants that to happen to their horse but that is what they are bred to do, what they love doing. They wouldn't jump these fences if they didn't want to," Thomson said.
Two other horses in the Grand National - Recite A Prayer and Cape Gentleman - were treated on course and taken away by horse ambulance for further assessment.
Climate and animal rights group Animal Rising, who demonstrated outside Aintree, said on social media their actions "aimed to prevent" the death of horses.
"The real reason the horse was running the race was so that people could bet on the horse, the jockeys could make money and so people could have a fun day out, and that doesn't seem like a good enough reason to put an animal in harms way," Ben Newman, a spokesperson for Animal Rising told BBC Radio 5 Live. "We disrupted the race for two reasons. One was to stop the race to stop a horse dying. Two, to have a conversation about our broken relationship back to animals."
British Horseracing Authority chief executive Julie Harrington has "robustly condemned" the actions of protestors and also announced a "painstaking" analysis will take place in an attempt to understand what caused three fatalities over the three days of the meeting.
"Our thoughts are with everyone connected to the horses who suffered fatal injuries this week. No one will be more affected by this news than the trainers, owners and stable staff who have provided these horses with first-class care and attention throughout their lives," Harrington said in a statement.
"The BHA and Aintree racecourse will now analyse the races in painstaking detail, as is the case every year, to build on our existing data and help us understand what caused these incidents.
"British racing works tirelessly to improve the sport's safety record and reduce avoidable risk. Every incident is reviewed by the BHA alongside the racecourse and other bodies. As a sport we have for years shown great determination and commitment to improve welfare standards by taking measured scientific, evidence-based, regulatory and education-based steps.
"It is for this reason that the fatal injury rate in the sport has reduced by over 1/3 in the last 20 years, to 0.2% of runners."
Reflecting on the protestors on the course, Harrington said: "We respect the right of anyone to hold views about our sport but we robustly condemn the reckless and potentially harmful actions of a handful of people in disrupting the race at a time when horses were in the parade ring.
"Those involved in British racing are rightly proud of our sport and the role it plays in providing an unparalleled quality of life for horses bred for racing. Love and respect for horses is at the heart of everything we do.
"The Grand National is and always will be an iconic sporting event and the actions of a small number of people will do nothing to diminish its huge and enduring international appeal."
Jockey Club chief executive Nevin Truesdale believes racing needs to be pro-active in the debate with activists.
"What this has done has bring the issues the sport was facing to the fore and allowed us to get out there and talk about them confidently - because we should," Truesdale told Racing TV's Luck On Sunday. "We should be out there talking about the measures we've taken, how much care these horses get, the changes we've made over the years, not just at Aintree, but everywhere and we should be proud of that."
The BHA works with World Horse Welfare on a number of matters.
"[Saturday] was a very sad day," said Roly Owers, chief executive of the charity, in a statement issued to the PA news agency. "From Aintree to television screens across the world, this year's meet was difficult to watch. The loss of Envoye Special, Dark Raven and Hill Sixteen is heart-breaking and we offer our condolences to their connections who we know will be devastated.
"Whilst it is true that accidents can happen anywhere - and the risks can never be removed altogether - jump racing poses specific risks that it has a responsibility to relentlessly reduce wherever possible. Whilst in the immediate aftermath of these events it is a time to reflect and review what has happened, it is clear to us that despite the changes made by Aintree and racing to date, much more needs to be done.
"In practical terms, this is an urgent reminder of the need to bring work on the Jump Race Risk Model to the fore. The model is a key tool to help inform how to make this and other jump races safer. Progress on this key project has not been quick enough and this needs to change now that racing has an agreement in place with the Royal Veterinary College to help take it forward.
"Overall, the types of questions that need to be considered are the number of runners, how to reduce the number of fallers, how to better manage loose horses and how to better manage the start. No one can accept fatalities as a certainty at any race and no one, least of all anyone in racing, wants to see what we witnessed in yesterday's Grand National."
Merseyside Police said a total of 118 people have been arrested on suspicion of criminal damage and public nuisance offences, with Aintree praising the response of both police and security.
Dickon White, who runs the track as North-West Regional Director for Jockey Club Racecourses, said: "There was a short delay to the start time for the Grand National, due to the reckless actions of a small number of individuals. The police and our security teams, who form part of a strong visible presence on course, dealt with the incident swiftly and decisively. The pre-race parade was cancelled as a result of the short delay.
"The Randox Grand National Festival sees thousands of people come to enjoy racing and a great atmosphere, with millions following on television, radio and online. While the actions of a small number of individuals were intended to disrupt the event, the safety and security of everyone on course will always be our number one priority."
Merseyside Police assistant chief constable Paul White said: "There's been a significant protest in relation to the running of the Grand National. This began earlier this morning [Saturday], there's been a number of protests outside and then that resulted earlier on today at about 5pm with numerous people trying to incur onto the course, which we, in partnership with the event organisers, and members of the public as well, have managed in the main to stop and and ultimately the event took place - albeit with a slight delay."
He said protesters tried to access the course from a number of points at the far side of the track.
He added: "The perimeter of the course is four to five kilometres long so you know, that is a significant resource required to try and cover every area of that. We put a proportionate policing plan in place and, by and large, we were able to stop the vast majority entering onto the course, a small number did get onto the course, but, very quickly, they were removed, again in partnership with the event organiser, private security and police officers and staff."
Traffic was also blocked by protesters on the M57 motorway at around the same time as activists attempted to get on to the racecourse at Aintree.
North West Motorway Police said on Twitter: "We have a number of people sat on the M57 at junction 2 northbound - motorway is closed."
National Highways said traffic was stopped in both directions on the motorway - between junctions one and two - shortly before 5.15pm, but by 6pm the southbound carriageway was reopened and northbound traffic was being diverted via a slip road.
There were delays of more than an hour on the road, which runs from the M62 to Aintree. Pictures showed protesters wearing pink T-shirts on the carriageway.
