Detectives are examining CCTV footage as they investigate a fight which left three men with stab wounds.
Three men were arrested after the incident outside the Mojo nightclub, in Thurland Street, Nottingham, at 4.16 am on New Year’s Day.
One man, aged 24, sustained injuries to his chest and back.
Another man, aged 18, was treated for a leg injury and a third man, also 18, suffered injuries to his chest. None of the injuries are currently believed to be life-threatening.
Detectives have been analysing hours of CCTV footage and speaking to taxi drivers who were working in Thurland Street at the time of the incident.
They have urged any other taxi drivers with information or dash-cam footage which could help with the investigation to come forward if they have not already done so.
Detective Inspector Chris Berryman, of Nottinghamshire Police, said: “We want to know exactly what happened in the moments before, during and after this incident and would like to thank those people who have already come forward with information.
“Due to a large number of people out enjoying the New Year celebrations, we believe there could be a lot of potential witnesses who have not yet spoken to an officer.
“Did you notice someone with injuries or bloodstains on their clothing in the early hours of New Year’s Day?
“This was a very serious incident and could have resulted in even more serious injuries.”
Two 18-year-old men and a 24-year-old man have been arrested on suspicion of affray.
Anyone with information is asked to call 101 quoting incident 240 of 1 January 2023. Alternatively, they can call Crimestoppers on 0800 555111.