The Ohio State Highway Patrol was investigating a single-vehicle crash in Marion County early Sunday morning.
Troopers said the crash happened on Smeltzer Road, just north of Marion-Cardington Road around 1:20 a.m.
Troopers said 35-year-old Jon Gwinner of Marion was traveling northbound on Smeltzer Road when his vehicle went off the right side of the road, stuck a large rock, spun around and struck a tree.
Gwinner was trapped in the car and had to be extricated by Fire and EMS personel on scene. He was transported to Grant Medical Center by Medflight and is listed in serious condition.
The passenger in the vehicle, 27-year-old Katherine Smith of Marion was also injured in the crash. Smith was taken to Marion General Hospital and later transferred to Grand Medical Center. She is expected to make a full recovery.
Highway Patrol said the cause of the crash was still under investigation.
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