A man was stabbed in Kettering’s town centre on Saturday night.
Areas of the town were cordoned off after the incident, which took place Tordoff Place between 10pm and 10.35pm.
The victim, a Kettering man in his 30s, was found having been stabbed in the torso.
A police spokesman said he was taken to hospital with injuries which are not believed to be life-threatening or life-changing.
Four teenagers - a 15-year-old boy from Wellingborough, a 16-year-old boy from Kettering, and 18-year-old man from Kettering and a 19-year-old man from Wellingborough - were arrested on suspicion of assault causing grievous bodily harm.
They have all since been released on police bail.
Police are appealing for witnesses or anyone with information about the stabbing to contact them. Witnesses should contact police on 101 or Crimestoppers anonymously on 0800 555111.