A man was left with a fractured eye socket, broken teeth and bruising following an altercation in a city centre street.
The incident occurred at around 11.30pm on Saturday, May 9 in Adelaide Street when the 28-year-old was involved in an argument.
DC Christopher Fisher, who is investigating, has urged anyone with information about the incident or anyone who recognises the two men to come forward.
Anyone with information is asked to call Herts Police on non-emergency number 101 or alternatively Crimestoppers on 0800 555 111.
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