Julian Thick, the Managing Director, said: "We are desperately sad at these two accidents and our sympathies are with the connections of both horses. When a horse gets hurt, everyone is deeply upset.

"Safety is the first priority for the organisers of the Grand National and we make every effort to ensure that everyone involved in the event is able to participate in safety.

"Horseracing is a sport that is very carefully regulated and monitored by the British Horseracing Authority but risk can never be completely removed. All horses and riders in the Grand National have to meet very high standards set by an independent panel of experts. The Grand National is a professional and well-organised race. Only the best horses and the best jockeys are allowed to enter.

"Since last year's race we have made further significant changes to the course and there have been four races run over the course without serious incident since then. After today, we will, as always, be looking at all aspects of this year's race to see how we can improve safety further.

"We work closely with animal welfare organisationsm, such as the RSPCA and World Horse Welfare to make sure we are up to date with the latest thinking and research regarding welfare and safety."

BHA Reaction

Professor Tim Morris, Director of Equine Science and Welfare for the BHA said: "We are very sad about the fatal injuries suffered by Synchronised and According to Pete in the Grand National.

"In both cases the horse incurred a fracture to the leg and the humane option was to put the injured horses down.

"The Grand National undoubtedly represents a challenge to both horse and rider. It has inherent risks, but, working closely with Aintree and other stakeholders, we do all we can to minimise these risks while maintaining the unique character of the race. We will examine closely the circumstances which led to both incidents.

"The key data from these accidents will be collated, as is the BHA's policy in the event of any serious equine injury. Each year the BHA and Aintree review all incidents which occur during the Grand National meeting and consider what measures can be taken to address the risk of a repeat in the future.

"The BHA takes its responsibility of looking after the welfare of horse and rider very seriously. We consult and work with recognised welfare organisations such as the RSPCA, SSPCA and World Horse Welfare. It is our stated objective to continue to reduce the number of injuries and fatalities which occur in racing."