A 21-year-old man who was stabbed in the early hours of Sunday morning in Nottingham remains in a critical condition in hospital.
The man was found near the Primark store in Long Row with a puncture wound to his body at around 1:45am yesterday.
An extensive search of the area has taken place and detectives are viewing hours of CCTV footage covering the city centre.
Detective Inspector Leigh Sanders, said: "We believe the altercation took place near to where, and not long before, the victim was found.
"It is possible that there were a number of people involved."
Nottinghamshire Police are appealing for witnesses and information in relation to the assault.
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