Three men were stabbed in an early morning fight between two groups of people in Bradford city centre.
The brawl happened just before 6am on Bank Holiday Monday in Sackville Street and five people were taken to hospital for treatment as a result.
Police said the fight happened after a stand-off in the street between the two groups.
The trio stabbed were aged 20, 19 and 17. Their injuries are not believed to be life-threatening.
Detective Inspector Stuart Lyons, of Bradford District CID, said: “Police were called to Sackville Street, Bradford at 5.53am on Monday after reports of disorder between two groups of people.
“Three men, aged 20, 19 and 17, were taken to hospital where they were treated for stab wounds, which were not believed to be life-threatening.
“Two further men, aged 23 and 18, were also taken to hospital where they were treated for minor injuries. A 24-year-old man has been arrested on suspicion of affray and is currently in custody.”
Councillor Imran Hussain, deputy leader of Bradford Council and portfolio holder for Safer and Stronger Communities, said: “This is a very serious incident and I understand police are investigating it, quite rightly.
“Those that are responsible for causing the unrest and those that were involved in this incident will be fully investigated and I ask for people to co-operate with police.”
Police want to hear from any witnesses or anyone who knows anything about the incident.
Det Insp Lyons added: “Inquiries are ongoing and anyone with information about this incident is asked to contact DC 5931 Mansell at Bradford District CID on 101 or Crimestoppers on 0800 555111.”
On April 27 last year – which was also a Bank Holiday Monday – a 19-year-old was stabbed on Sackville Street at about 4.20am. The victim suffered minor stab wounds, police said at the time.