WSOC reports the officer was driving on East Woodlawn Road just after 1:30 a.m. when she heard gunshots, officials said.
She pulled over in the parking lot of a Days Inn, and when she got out of her patrol car, she saw a man with a handgun, police said.
The officer said the armed man's actions gave her the "impression that her life was in jeopardy," so she fired her gun and hit him in the leg, according to Chief Kerr Putney.
When more officers arrived at the scene, they applied a tourniquet to the man's wound.
Paramedics took the man to Carolinas Medical Center.
Investigators found the man's gun at the scene, officials said.
Witnesses told reporter Mark Barber that they have video of the shooting, and it is being reviewed by police.
The officer was not injured and is on administrative leave, which is standard procedure after a shooting.
Also following standard procedure, the Internal Affairs Bureau will conduct a separate investigation to decide if department policies were followed.
The names of the officer and the injured man have not been released.
Anyone with information is asked to call 704-432-TIPS or Crime Stoppers at 704-334-1600.
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