Forty horses were in the barn when the fire started. It was spotted by a neighbour who freed the animals and called the emergency services, police said.
But two horses, trapped by the smoke and flames, died from their injuries inside and two more that did manage to escape had to be put down later.
Four fire engines and 29 firefighters took several hours to bring the blaze under control. An investigation into its cause is under way. A police spokeswoman said: "It is still too early to say if foul play was involved. It is still very hot and damping down is going on."
Meanwhile, stable staff were beginning the long process of clearing up. It is thought the horses that died were four of Old's younger horses but they had not been named last night.Reuse content