The sight, the smell and the sound that greeted investigators at Bank Top Stables was unimaginable.

Even people who had been involved in the mass culling of cattle during the foot-and-mouth outbreak four years earlier were not prepared for this.

The smell was stomach-churning, and the sound of thousands of maggots devouring carcasses will stay with the witnesses forever.

Hardened cruelty investigators were physically sick and others refused to enter because of the horror in the stables, where animals appeared to have been simply locked up and left for two months to die.

The rotting bodies of about 30 animals were found in the dark outbuildings on the edge of Trimdon, County Durham, last summer. It took a council environmental health team and specialist contractors ten days to clear the filthy abandoned site.

And it took investigators from Durham Police and the RSPCA several weeks to draw up a list of the dead - even though it is still not known exactly how many animals perished.

The remains of at least 13 horses and ponies, 11 hens, four dogs and a rabbit were found, but experts struggled to provide a definite figure because of their state of decomposition.

Rotting carcasses and bones were still being found a week after police and RSPCA officials broke into the property, following complaints from locals about the smell.

Inspector Mark Gent, of the RSPCA, described the discovery as the worst he had ever seen, while one of the clean-up team recalled the horror of the find.

The worker said: "It was absolutely disgusting. I've been involved in clean-up operations and moved dead bodies before, but never experienced anything like this.

"This has really turned my stomach. Nothing has ever got to me in the same way. I'm accustomed to the smell of death, but this has been beyond belief."

He added: "The smell was overpowering - it stuck to my clothes and I had to throw them away at the end of the first day.

"There were maggots, flies and mice swarming all over the place. The carcasses were all at different stages, some were just bones and others had turned to liquid."

Insp Gent said: "The stench was such that I just knew that something was dead. I have smelt it before, sadly, but you know that smell and I knew instinctively there was something wrong.

"It was an awful find and shocking to see how many animals died in there."

Members of the specialist team wore full body suits and face masks to shield them from the smell as they set about clearing the carnage.

The animals had been left with no food or water, and shared sodden bedding - but one by one, they starved to death.

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