A 10-year-old girl was seriously injured when she was struck by an ambulance on an emergency call-out.
The crash happened in Low Wood Road, Bulwell, in Nottingham at about 18:30 GMT on Sunday.
Police said the full extent of the girl's injuries was still being assessed and officers urged witnesses to come forward.
East Midlands Ambulance Service confirmed the vehicle was responding to a call-out when the crash happened.
An ambulance spokesman said their thoughts were with the girl's family.
The road was initially closed for police to investigate at the scene, but it was reopened in the early hours.
No further details of the crash have been released.