The shooting happened at about 2:11 p.m. at 10103 Tanner Road on Saturday.
The Precinct 6 deputy was conducting personal business when a man with a face covering entered the building, according to police.
Police say that the off-duty cop fired his gun at the masked suspect, but it's unclear if the suspect was hit. The suspect then fled in a black BMW car.
Although details are still limited, there are no injuries reported at this time.
The deputy, who shot the man, has six years of experience with the constable's office and will be placed on administrative leave upon investigation.
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