A car driver suffered serious leg injuries in a collision with a marked police vehicle in south Devon.
A Ford Ka and a Ford Focus patrol car collided at 23:15 BST near California Cross on Friday.
Police said the patrol car had not been responding to an incident. The force has referred the crash to the IPCC.
The car driver was airlifted to Derriford Hospital in Plymouth for treatment. The police driver suffered minor head and body injuries.
The collision has been referred to the Independent Police Complaints Commission for investigation.
Devon and Cornwall Police declined to comment any further until a decision on whether to investigate had been made.