Police and RSPCA officers will this week launch a major investigation into the violent deaths of 39 pet cats and 10 rabbits which have had their heads and tails removed with a cleaver.
The cats, some of which have also had their blood drained, have been laid out in a ritualistic fashion in gardens near their owners' homes. Many of the animals have been found with their heads placed beside the bodies or their brains removed. Others have simply been decapitated and their heads taken away as trophies.
Psychologists have warned that the pattern of the deaths - which began in February but escalated last month - is reminiscent of human serial killings, where trophies are removed before the bodies are displayed in prominent positions.
They fear that the killer may be a disturbed teenager or young man involved in satanic ritual. They say he may move on to harm humans later in life unless he receives professional help.
"This scale of ritualised cruelty is rare. It's very reminiscent of the way serial killers behave," said Susan Hope-Borland, a forensic psychologist who specialises in criminal behaviour. "With serial killers there's an organised set of events. They arrange the body in a certain way and a trophy is taken. There is research to suggest that people who go on to commit horrendous crimes in adult life have a history of the ritualistic killing of animals in childhood and adolescence."
The pets, which have all been taken at night, are thought to have been killed quickly before their heads and limbs are removed with a cleaver or other sharp instrument. The killings have baffled and shocked even hardened RSPCA inspectors, who say they have not experienced cruelty on this scale before.
"People have come home after work to find that their pets are dead and decapitated. I have never seen anything quite like this in my career," said Nigel Shelton, who is leading the RSPCA investigation. "No one can recall anything quite like this in the past. It could be linked to black magic, we don't know.
"People are keeping their cats indoors. It almost seems to be premeditated. It seems that there is one person behind this but it is becoming so widespread that it could be a group. The police are involved. It's crossing every division in the Met."
The killings have all taken place in in clusters in north, south and east London and the South East. They increased in frequency during September and October with the number of cats reported missing also higher over the same period.
Last week, 10 cats were found with the same trademark injuries. The RSPCA fears that up to 100 cats could have been killed in this way and is appealing for people to report clues that could lead to the arrest of the killer.
Owners, some of whom have had autopsies confirming human involvement in the deaths, have been traumatised. Mabel, a lively black cat which was rescued as a two-year-old stray by her owner, Yvonne Trumble, a bereavement counsellor, was found in a neighbour's garden in north London. Ms Trumble believes the cat, which was wary of humans, was chased before being caught. She has three other cats and is afraid to let them out at night until the killer is caught.
"All I know is that she died at the hands of humans. It was so horrible. I was upset for days," she said. "Once the initial horror wears off, it leaves this dreadful feeling. It leaves the feeling of not trusting anyone. You teach your pets not to trust human beings. Not in your wildest dreams do you think someone will get your cat and do such a terrible thing. She didn't need to end her life like that."
Parallels have been drawn with the mysterious series of horse mutilations which have been linked to satanic cults.
Another cat owner from Weybridge in Surrey was horrified to find that Daisy, her eight-year-old long-haired tortoise-shell tabby, had had half her head and tail removed after apparently being pursued by her killer into a road. A post-mortem showed that someone had removed her brain, although there were no traces of blood on the body.
"She was a beautiful, beautiful cat. She had the most wonderful tail, but her tail had gone and half her head had gone, but there was no blood at all," said her owner. "The vet said someone did this to her. I can't believe anyone could do this. There is some sicko out there."
MPs have appealed for the police to take the matter seriously and to give it top priority despite the fact that it involves animals.
Angela Smith, MP for Basildon, said: "This series of killings is horrific and very distressing. The perpetrator, or perpetrators, are dangerous people. I know it's very difficult for people to be vigilant about cats, which are very independent creatures. It's a very worrying trend indeed. The killer must be caught."Reuse content