A man is being questioned about a fight on Windsor Road.
Jersey Police were called to the old Caesarea court just before midnight last night (Thursday 6th June).
A 33 year old was arrested at A& E on suspicion of Grave and Criminal Assault and remains in custody.
Two other men suffered minor facial injuries.
Police are trying to trace an unknown fourth man they think was involved.
Anyone who saw what happened is asked to call 612612, Crimestoppers anonymously on 0800 555 111 or via their online form at crimestoppers-uk.org