A man was stabbed suffering serious injuries after a fight between four men spilled out on to the street.
Police said the incident started inside an address in London Road, Hilsea, at 4.40am.
The men moved into the street where a 23-year-old man from Southampton was stabbed. He was taken to hospital with serious injuries.
Detective Sergeant Abigail Leeson, said: ‘I would like to speak to anyone who witnessed this incident or anyone who has any information.
‘If you saw or heard what happened please call us as soon as possible on 101 quoting incident number 44180215622.’
A 25-year-old man from Southampton and a 27-year-old man from Portsmouth have been arrested on suspicion of causing grievous bodily harm with intent and are currently in police custody.
Anyone with information should contact Hampshire Constabulary on 101 quoting 44180215622.
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