Officers are appealing for information after a teenage boy was injured in Bolton on Wednesday.
Police were called to a report of an assault on Moss Bank Way at around 3.20pm on Wednesday 17 March.
Officers attended and enquiries established that a boy had been assaulted following an altercation.
The victim - a 15-year-old boy - was taken to hospital with a serious cut above his eye, believed to be caused by a small unknown object. He has since been released from hospital to continue with his recovery from home.
A 15-year-old boy was arrested later that day on suspicion of assault and he has since been released on bail.
Enquiries are ongoing and police wish to speak to anyone in the area at the time of the incident to aid their investigation.
Police Sergeant Helen Atherton, of GMP's Bolton district, said: "This nasty incident saw the victim suffer a serious cut just a matter of centimetres above his eye and we are keen to make sure we find out exactly how this occurred.
"We know there were a large number of people in the area at the time who may have witnessed this incident, and I ask any of those people to do the right thing and come forward.
"It is also very likely that some people may have mobile phone footage of the incident and it is so important we hear from anyone who may have filmed the event so we can piece together the circumstances."
Anyone with information should call 0161 856 5761 quoting incident 1727 of 17/03/2021. Details can be passed anonymously to the independent charity Crimestoppers on 0800 555 111