A teenager is in a serious condition in hospital after falling from his mini moto bike.
The 15-year-old suffered life-threatening head injuries after the accident as he was riding along Hodges Gap in Cliftonville at around 4pm on August 11.
Now police are appealing for witnesses to the crash, in which no other vehicle is thought to be involved.
PC Guy Miller, leading the investigation, said: "Reports suggest that two teenage boys were riding mini moto motorcycles along Hodges Gap in Cliftonville.
"One of the boys came off his bike and sustained very serious head injuries.
"We are keen to investigate the circumstances into the collision and are asking for anyone that may have witnessed the incident to contact us to help with our enquiries."
He said the boy was, thankfully, wearing a crash helmet, but he still suffered serious head injuries.
He added: "This incident is a tragic reminder to parents and youngsters that these motorcycles are not a toy and should be used with care."
Anyone who can help the police should contact PC Guy Miller in the Serious Collision Investigation Unit on telephone 01622 798538.