The image shows a white SUV, similar to one an officer might be driving, except it had flashing purple lights instead of blue. The suspected impersonator is seen wearing a law enforcement uniform as he stands beside a car.
The Facebook post on Tuesday already has thousands of shares.
“This is the second time I have seen this white SUV (pull) someone over between Coldwater and Senatobia on I-55. I’m sorry but if this person ever tries to pull me over, I'm not stopping. ... I'm not taking purple flashing lights "seriously," the post said.
Mississippi Highway Patrol Troop E thanked the woman who posted about the incident and brought it to their attention.
The agency said "the subject has been identified and the situation is currently being addressed."
The alleged police impersonator was eventually stopped by Tate County deputies, but they let him go because they didn’t have any information on the accusations against him, police said.