Their deaths were portrayed as a Romeo and Juliet-style suicide pact, but it has emerged that Harry Horse, the acclaimed children’s author and illustrator, killed his terminally ill wife in a frenzied knife attack that left her with more than 30 wounds.

The 46-year-old then killed the couple’s pets before stabbing himself 47 times and bleeding to death.

When their bodies were found in their remote bungalow in the Shetlands in January last year, reports suggested they had died in each others’ arms after overdosing on painkillers.

Horse, best known for his children’s book The Last Polar Bears, which was turned into a television cartoon starring Sir Nigel Hawthorne, was facing financial difficulties.

His 39-year-old wife Mandy, who suffered from multiple sclerosis, had been confined to a wheelchair.

However, The Sunday Times Magazine today reveals that when the couple was found the house was a scene of carnage. The doctor who attended said the sight was the most disturbing he had witnessed.

Horse is said to have taken a cocktail of drugs and, according to the last people to see them alive, he was in a demented state on the eve of the deaths, proclaiming: “It’s a wonderful night for a killing.”

He stabbed his wife with such ferocity that the blade broke off in her body and he collected a second knife to continue the attack. Her arms were covered in injuries sustained as she tried to fend him off. Leaving her to bleed to death, Horse killed their dog and cat before turning the knife on himself.

The brutal circumstances of their deaths were not made public because police and prosecutors decided that a fatal accident inquiry was not in the public interest. Under Scottish law, such inquiries are mandatory only if a death has occurred at work or in police custody.

The truth of their deaths has emerged after Mandy’s family decided to go public to stop rumours circulating in the tight-knit Shetland community.

The couple’s families initially agreed for them to be buried together. It is understood they are now discussing whether the bodies should be exhumed and buried in separate plots.

Horse, whose real name was Richard Horne, published his first children’s book, The Opopogo – My Journey With The Loch Ness Monster, in 1982. The Last Polar Bears, published in 1996, won critical acclaim and Horse also contributed political cartoons to national newspapers.

He met Mandy in Shetland while touring with his rock band Swamptrash. In 2004 she was diagnosed with MS, which Horse found difficult to cope with, telling friends his life had become “a living hell”.

The couple’s last visitors were two brothers from New Zealand who found Horse in an agitated state. Mandy was distressed and wanted them to stay. The next day they returned to find Horse and Mandy’s bodies on her bed and the room spattered with blood.

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