A former show horse "enjoying a happy retirement" has died following an attack in her paddock.
Owner Tracy Grantham said she found 17-year-old Sindy with a gaping wound to her neck and shoulder in her field in the Mendham area of Suffolk on Tuesday.
The injury was so severe she had to be put down. Police are investigating.
"To know that someone has done this to an innocent creature beggars belief," said Ms Grantham, who bought the thoroughbred cross four years ago.
"She didn't trust people - there was something in the past - but we taught her to trust people and that was her fate."
'Arrived to silence'
She said Sindy had failed to react when she and her teenage daughter tried to stable her for the night.
"We can usually hear her screaming. She always lets us know she is ready for bed, but we arrived to silence.
"We immediately knew something wasn't quite right."
Struggling to walk, Sindy was helped back to her stable.
"I assumed it was a horrific accident, but the vet said 'I think we need to contact police, this is not an injury the horse has done to herself'," Mrs Grantham said.
"She was given a heavy dose of painkillers but it was evident the extent of the injuries were irreparable."
Sindy had been showed by the Granthams and used for show-jumping and eventing until April.
"We decided we were going to wind it down and she was enjoying a happy retirement in the sun and getting fat with her field buddy Chance.
"We are absolutely mortified as a family.
"Why would somebody want to do that?"
Suffolk Police said it was investigating the "disturbing" attack, which happened between 16:00 and 18:00 GMT.