A dog has died after it was mauled by two other animals described as Staffordshire bull terriers in an attack in Lynn on Thursday morning.
Police said the incident had happened as the dog was being walked by its owner behind Russell Street between 10am and 10.30am when it was attacked by two other dogs.
The man walking the Terriers made a comment to the owner of the injured dog before leaving.
The injured dog was taken to the vets where it died on Saturday. The owner of the injured dog also suffered minor injuries to his wrist and thumb during the incident.
It is believed there may have been people walking in the area of Russell Street and Hospital Walk around the time of the attack and officers are keen to hear from anyone who may have witnessed it.
The man walking the terriers is described as being in his 50s, of slim build, with a pale complexion, blue eyes and wearing a woolly hat.
Anyone who may have witnessed the incident, or who may can help officers trace the owner of the two Staffordshire Bull Terriers, should contact PC Faye Stocker on 101.