The Ohio State Highway Patrol was investigating a single-vehicle crash in Knox County.
Troopers said the crash happened around 9:45 p.m. In the 20400 block of Coschocton Road.
OSHP said the driver struck a deer, lost control of their vehicle and struck a business.
Troopers said the car knocked over a wall of the building and there was damage to the business.
The driver was taken to Grant Medical Center by Medflight and was listed in critical condition.
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