This happened to an elderly CAVALIER . An electric 'invisible fence' (actually a shock collar set to work on certain boundaries) not only is considered unacceptable and potentially cruel by every animal welfare organisation I know of in the US and UK and Ireland, they do NOT keep your dogs safe from anyone and anything that wants to come in and take them or harm them. In this case either someone took, attacked and killed this poor old cavalier or animals just came in and took him.
A veterinarian called authorities to report the incident after the mutilated animal was brought to her office to determine what might have happened, according to the report. The vet said she believed the dog had been stabbed at least once, and then the fur coat was cut from its body.
The owners said they let the dog, which was nearly deaf, out of their house — in the 700 block of Oak Shores Drive in the Cross Roads area — into the yard along with their three other dogs. The owners have an invisible electric fence that keeps the dogs in the area, they said. Later they discovered that the spaniel, “Bonny,” was missing and began to search for him.