Thames Valley Police is appealing for information after an assault and affray in Milton Keynes on Wednesday (27/4).
At around 4.15pm, a group of four youths carrying knives and machetes chased another group of three youths out of the underpass next to Greenleys local centre off Ardwell Lane.
The armed group chased the other group in front of the shops on Ardwell Lane and attacked one of the youths, causing a stab wound to his leg.
The armed group then left the area in a taxi.
The victim, a teenage boy from Milton Keynes, was taken to Milton Keynes University Hospital but has since been discharged.
Four 15-year-old boys, three from Milton Keynes and one from Bletchley, have been arrested on suspicion of affray, possession of an offensive weapon in a public place and causing grievous bodily harm with intent. They have been bailed until 25 May.
Detective Inspector Jason Simpson, of Milton Keynes CID, said: “I would like to reassure the community that we are investigating this assault thoroughly and robustly as we will not tolerate knife crime in Milton Keynes.
“We have already made four arrests but I am appealing for any witnesses or anyone with information about this incident to please get in touch.
“We want to talk to anyone that was there even if they think they cannot assist us to get a full picture of what happened and its impact.
“If you have any CCTV footage in the area or any dash-cam footage if you were in the area around the time, I’d also ask that you check any recordings in case it has captured something that could assist our investigation.
“To contact us, call 101 or make a report on our website, quoting reference number 43220180968.
“Alternatively, you can provide information anonymously to the independent charity, Crimestoppers, by calling 0800 555 111 or via its website.”