A post-mortem examination has revealed that a man who was found seriously injured in Bilborough died from a gunshot wound.
The victim, who has not yet been formally identified, was taken to the Queen's Medical Centre in Nottingham but later died.
A 32-year-old man has been arrested on suspicion of murder.
Inquiries are ongoing to establish what happened.
More top news
East Midlands weather: Staying mild with cloud building from the west
Police investigations are continuing into a stabbing in Leicester in which a man was critically injured.
Police are investigating after a man was slashed with a pen knife during a fight on the urban beach in Nottingham city centre.