A taxi driver was taken to hospital after his vehicle was involved in a collision with a police car.
The police car was being driven by an officer on duty and responding to an incident when the smash happened on Upper Hanover Street, Sheffield, at 7.45pm on Tuesday.
The taxi driver, a 45-year-old man, was taken to hospital with minor injuries.
The road was then sealed off to other traffic with police cars parked at either end.
A South Yorkshire Police spokeswoman said the incident was being investigated by the force’s professional standards department.
“The investigation is being overseen by the professional standards department in line with policies and procedure,” she said. “The officer was on duty and responding to an incident, and has not been suspended.”