British Police have confirmed the dog which killed Liverpool boy John-Paul Massey was an illegal breed, Sky News reported.

Officers said the animal that mauled the 4-year-old to death outside his grandmother's house was a pit bull terrier-type animal outlawed under the Dangerous Dogs Act, Sky News reported.

Police in Liverpool have already admitted they failed to follow up a complaint about animal breeding at the house where the boy was attacked in the Wavertree area of the city.

His grandmother, Helen Foulkes, was hurt as she tried to stop the dog, called Uno, savaging the child.

The 63-year-old, who suffered bites to her legs and body, was taken to hospital but later discharged.

Dog handlers and armed response officers arrived at the house and shot the dog, which was described as being highly agitated.

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