White House correspondent for Time Magazine Brian Bennett originally mentioned the slight on his Twitter account, before the message was picked up by Lightfoot.
Lightfoot, a Democrat, followed up with her own tweet which referred to McEnany as "Karen" — a pejorative term that has come to prominence to label a demanding, middle-aged white woman who displays a sense of overbearing entitlement in various societal confrontations.
"Hey, Karen. Watch your mouth," the mayor wrote.
Fox News reached out to the White House press office but did not receive a response to the request for comment.
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