A nine-year-old boy is fighting for his life in hospital after he was knocked over by a car near Hartlepool Marina.
The schoolboy was with a group of friends at the time of the collision in Marina Way, at shortly before 5.45pm Cleveland Police said.
The youngster was struck by a grey Range Rover and off-duty probationer police officers who were nearby, rushed to help him.
They administered emergency first aid at the roadside until paramedics arrived to take over.
The boy was then taken by air ambulance to James Cook University Hospital in Middlesbrough.
He is said to have suffered life-threatening injuries in the incident and his condition is described as critical.
The youngster’s family was said by police to be keeping vigil at his hospital bedside.
Officers are trying to piece together what happened in the run-up to the crash.
They believe the boy was with other young people at the time, and are appealing for all of them to contact police as soon as possible.
The accident was attended by a large number of emergency services.
Three road ambulances and numerous police cars were assisting with the aftermath of the incident
The North East Air Ambulance landed in the carpark in front of Boots the chemist on Anchor Retail Park.
The road was completely blocked following the crash, which happened about tea time, causing long tailbacks and affecting bus services.
A police spokesman said: “At 5.45pm police received a report of a nine-year-old boy who was in collision with a grey Range Rover on Marina Way in Hartlepool.
“Off-duty probationer police officers were on the scene and administered emergency first aid prior to the attendance of ambulance staff.
“The boy was taken by air-ambulance to James Cook University Hospital with life-threatening injuries and his condition is described as critical.
“The boy’s family are in attendance at the hospital.
“Police believe the boy was with several other young boys and girls at time and are appealing for all who may have been with him or anyone who witnessed the incident to contact police on 101.”