A large group of people, some armed with weapons, were involved in a confrontation outside a pub in Pill which left one man with head injuries.
The incident took place outside The Kings Head pub, in Heywood Road, shortly before 11pm last night (Friday).
One man suffered a head injury and was treated in hospital before being discharged.
Police area now appealing for any witnesses or anyone with information about the incident to come forward.
Officers have been carrying out house to house enquiries and reviewing CCTV from the area.
A spokesman for Avon and Somerset Police said: "We’re keen to speak to anyone who saw what happened or who has information about who was involved.
"We’d also like to talk to anyone who saw any cars leave the area around the time as well as anyone who was driving past and has dash cam."
Anyone with information is asked to call 101 and provide the call handler with the reference 5221136661, or call Crimestoppers anonymously on 0800 555111.
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