An 18-year-old man has died in hospital following a fight in Cambridge city centre.
Police said the man was injured in the early hours near to the Grand Arcade entrance in St Andrews Street.
A 23-year-old man from north London was arrested on suspicion of committing grievous bodily harm but has now been re-arrested on suspicion of murder.
Another man, aged 20, from Cambridge, has been arrested on suspicion of causing grievous bodily harm.
Police said the fight was reported at 03:18 GMT.