A man has been arrested on suspicion of attempting to murder a police officer in a hit-and-run crash.
PC Christopher Burnham, 48, was struck by a Mini he was trying to stop in Holbrook Lane, Coventry, just after 14:45 BST on Wednesday.
He was taken to hospital with a fractured skull, bleed on the brain and a shattered knee.
West Midlands Police said a 37-year-old man was arrested on Friday evening and is being held for questioning.
Detectives said the driver involved in the crash left the scene and the Mini was found abandoned a short distance away.
PC Burnham, who is married and has a 10-year-old son, has been with the West Midlands force for 25 years and has a number of commendations.
Colleagues said he is likely to have to remain in hospital for some time.
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