At least 38 animals are known to have died in the stables.

An investigation is continuing to establish how the animals came to be locked in Bank Top stables in Trimdon.

The death toll included 16 horses, 11 birds, six dogs and a rabbit.

Inspector Mark Gent said on Monday that three dogs had survived the ordeal, possibly living off the bodies of the other animals.

The RSPCA were alerted on the afternoon of Sunday, 29 May, after a member of the public became concerned for the welfare of the animals.

I have never seen anything on this scale before Mark Gent, RSPCA

Mr Gent said: "I received the call from our call centre.

"When I got there, I smelt a terrible smell and knew there was something wrong and phoned the local police who attended and we broke in and found quite a shocking sight.

"I have smelt it before, sadly, but you know that smell and I knew instinctively there was something wrong."

He said tests are being carried out on the animals' remains to establish how long they had been there and the cause of death, but he said it would be a long process.

Mr Gent said so far 38 animals and birds are known to have died: "There were varying degrees of decomposition but those are the animals and bones we found.

"Three dogs did survive - we think they were living on bags of dog food that had been ripped open but there were also bones of carcasses nearby, so they may have been living off other animals as well.

"I have never seen anything on this scale before."