(CNN) A Detroit police officer -- who referenced "black girl magic" as he filmed a woman he pulled over walk home in the cold -- has been demoted, the police chief said in a news conference Thursday.

Chief James Craig said the officer, a corporal in the Detroit Police Department, stopped the woman for expired registration. Her vehicle was towed, and as she walked to her home in the cold the officer posted a video on Snapchat saying "Bye Felecia."

The officer did offer her a ride, Craig said, but she declined.

Craig said the officer also made a reference to Black History Month, which he called even more problematic.

The video included a "Celebrate Black History Month" filter, with the caption "What black girl magic looks like," CNN affiliate WXYZ reported.

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