Animal lovers have reacted with horror after a stallion was mutilated and killed in what police called a "sickening" attack, the second on a horse in the space of a week.
The first horse, Barney was attacked in Carmarthenshire, Wales on 5 January.
Linda Vickerage, a nurse, discovered the remains of seven-year-old Welsh pony Barney when she went to give him and her other pony their evening feed at a field in Whitland.
Wales Online reported that when police and a vet examined Barney they found he had had his eyes removed, his mouth slit, his ear cut, and been slashed along his body, exposing his organs.
A spokesman for Dyfed-Powys Police said: "Investigations are continuing, we are in contact with the owner of the horse."
Now a two-year-old horse, called Eric has been found in Cornwall with his genitals, an eye and teeth cut out after the attack in a field in Cornwall. Police are investigating whether he was drugged before being attacked.
His owner Dawn Jewell said she had lost "her baby", a Friesian horse she had been wanting since she was a child. Animal lovers have been making their feelings of horror known in large numbers via Twitter, including the BBC horseracing presenter Clare Balding.
Ms Jewell told the BBC that she came across the horse and thought he was just lying on the ground. When she realised what had happened she called a vet and the police.
"He was my baby, I absolutely adored him," she said.
"I looked for years for one but this one wasn't right and that one wasn't right, when I found him I knew he was the one for me."
A mare and a foal in the field with Eric were left unharmed, Devon and Cornwall Police said.
They are warning people in rural areas to remain vigilant to anyone acting suspiciously and if they have any concerns contact them.
Detective Inspector Tony Blatchford said: "This is a particularly sickening crime, one that I've never come across before involving such extensive mutilation.
"Detectives are following lines of inquiry to try to identify the offender and I'd ask all horse and livestock owners to be particularly vigilant and report anything suspicious to police."
Presenter and journalist Balding, who fronts the BBC's live racing coverage, including the Grand National, Royal Ascot, the Derby and l'Arc de Triomphe, was informed of the incident by followers in Cornwall.
"Have been alerted to this by various folk in Cornwall. Horrific attack. Horse owners beware," she wrote.
The RSPCA said one of its officers would be examining the horse with a vet today to try to find out more details about the attack, including whether the mutilation happened before or after the horse died.
"This is a shocking incident and I cannot imagine what would cause someone to carry out such a cowardly and barbaric act," a spokeswoman said.
"I would urge anyone with information to contact either the police or the RSPCA."
Anyone with information about the Cornish attack can contact Devon and Cornwall Police on 101 quoting reference GP/12/66.