Thieves broke down a six-foot fence to steal two male Shetland dogs.
The incident happened on Sunday (January 31) between 5pm and 6pm in Almondsbury.
One dog was later recovered after it was found running loose near the Portway in Bristol days later.
Avon and Somerset Police are appealing for help to trace the remaining dog.
The three-year-old dog (pictured) is still missing.
Police said in a statement: "If you know his current whereabouts or have any other information which could help the investigation call 101 quoting reference 5221021985."
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