An off-duty police officer was left with "serious facial injuries" after being knocked unconscious.
The officer was attempting to resolve an incident in which a man was being abusive to two women in Queens Road at around 4am on Sunday (April 28).
The man involved punched the officer in the face and knocked him out.
The offender ran off and his victim was taken to hospital with a broken jaw and forced to undergo surgery.
His attacker is described as mixed race, 5ft 10ins, with short black hair.
He was wearing a black t-shirt and blue jeans.
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Avon and Somerset Constabulary is now appealing for witnesses to the "despicable" assault.
DI Dave Lewis said: “The officer was trying to break up an escalating incident involving a man and two women when he was attacked out of the blue.
“It was an unprovoked and despicable act which has left him with some serious facial injuries.
"It’s being investigated as an offence of causing grievous bodily harm.
“We’re reviewing CCTV footage from the area and are looking for witnesses to this incident to come forward. We’d especially like to speak to the two women who were involved in the initial incident.
“We’re providing full support to the injured officer and his family as he recovers from his injuries.”
Inspector Andy Roebuck, Avon and Somerset Police Federation Chair, said: “I was horrified at the level of violence used during this attack on a police officer who was simply doing his duty and being human by helping a person in need.
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“Attacks on police officers and other emergency workers cannot be tolerated and this coward should be brought to justice.”
Anyone who can help with information on this incident is asked to call Avon and Somerset Police on 101 and give the call handler the reference number 5219092274.
Independent charity Crimestoppers can also be contacted 100 per cent anonymously on 0800 555 111 or via their Anonymous Online Form.
