Police are investigating an incident in which a dog, thought to be a staffordshire bull terrier allegedly attacked and bit the head off another family's pet pomeranian.

A photograph of a bloodied dog owner struggling to control the animal was posted on social media by Gemma Antell, a mother of three from Warrington who says that her pomeranian, Elvis, was decapitated by what police believe was a white staffordshire bull terrier.

"If it was capable of doing that to another dog then you would have to be afraid for what it could potentially do to a child's arm, or worse," said Antell.

The incident happened outside the home of her mother-in-law on Saturday when the larger dog was said to have pulled its owner into the front garden of the house and attacked the other animal. Several young children were present at the time and the photograph was taken by the father of a four-year-old girl.

Antell added: "It was all the more shocking due to the fact that the woman who had the dog, and a man who was with her, just walked away.

"The dog just spat out the head of Elvis on the street."

"I don't believe that there are bad breeds. Dogs do things because of the way their owners treat them, but this dog really needs to be located," added Antell, a blogger who has worked with dogs and cats at a kennels company.

Cheshire police said the force was investigating the incident and asked for any witnesses or others who knew the whereabouts of the dog to call them on 101 or ring Crimestoppers anonymously.