A Chihuahua was killed by another dog dangerously out of control in Cassiobury Park.

During the attack, at around 3.45pm on Tuesday, December 1, six-year-old Mimi was mauled by what her owners believe to have been a Staffordshire Bull Terrier or Boxer being walked in the park at the same time.

At the vets Mimi died as a result of multiple and significant injuries.

She was being walked by her family, including two children, with their other pet an 18-month old French bulldog called Rocco.

They attempted to remove the dog that was attacking Mimi, but one of the family was bitten on the arm causing a puncture wound.

The dog then attacked Rocco.

A woman and a man were with the offending dog. The woman drove the family and their pets to a vet, but drove away before exchanging details with injured dog’s owner.

Rocco sustained lacerations. The vet bill amounted to around £400.

The offending dog is described as light brindle in colour with short hair.

The man who was with the dog is described as white, aged in his 40s or 50s, of large build and around 6ft tall. He had a round face, short light hair and blue eyes. He was wearing a brown leather jacket with dark jeans.

The woman who was with the dog was driving a silver, estate-style vehicle, which was parked in the car park off Gade Avenue. It is believed the vehicle had a taxi plate on it.

She is described as being white, aged in her 40s or 50s, of large build and with blonde hair. She was wearing a brown jacket and brown hat.

Just prior to and after the incident, the injured dogs’ owners spoke with a woman who was walking with three dogs, which looked similar to German shorthair pointers. Police are keen to speak with her as she may have information that could assist their investigation.

PC Naysha Foley said: “Understandably the owners of the injured dogs are devastated by the death of their pet, particularly when the people in company with the offending dog failed to exchange contact information.

“We would like to identify the people walking with the dog as soon as possible. If you believe you know their identity, to whom the dog belongs or if you witnessed the incident, please contact me.”

Alternatively, contact Crimestoppers anonymously on 0800 555 111 or through their Anonymous Online Form at www.crimestoppers-uk.org.