Police were called at 6.59pm yesterday evening to the junction of Copnor Road and Amberley Road.
They were responding to concern for the safety of a man in his 50s.
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Officers and ambulances attended and the man was taken to Queen Alexandra Hospital where he was sadly pronounced dead.
His next of kin have been informed.
At this stage, the death is not being treated as suspicious and a file will be prepared for the coroner.