A gang stabbed a dog to death then slashed its disabled owner with a knife, police have said.

The 38-year-old woman, who can walk only with crutches, struggled out to her back garden to find the youths attacking her pet Yorkshire terrier, Willow, on Sunday.

The pet was stabbed to death on the ground and the woman was forced back inside her home at knifepoint, suffering "numerous" lacerations to her body.

A 13-year-old boy has been arrested on suspicion of assault and causing cruelty to animals and remains in custody.

Merseyside Police confirmed that four men - two aged 21, one 19 and the other 24 - have also been arrested over the attack in Knotty Ash, Liverpool. An 18-year-old man arrested on the same charges has been bailed pending further inquiries.

Detective Inspector Rob Hill said: "This was a particularly vicious attack that resulted in a woman being both physically and verbally assaulted. We are trying to establish the motive for the attack and speaking to as many people as possible in the area to catch the offenders."

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