The whole thing started when a fan tweeted out, "'You're gonna delete that, right?' Literally [NBC Chicago PD] when [NBC Chicago Fire] tweets something they don't like. Or vice versa," tagging both shows.
Chicago P.D. retweeted the tweet and added, "Literally us every time Fire says "lit."
Not one to just stand around and let their good name be sullied like that without sticking up for themselves, Chicago Fire fired back, "[At] us next time, thanks!"
Fans of the shows have been following the beef and are showing up for it.
One person wrote, "We don't like when Mom and Dad fight" and another pleaded, "Please don't fight!"
Things seemed to have cooled off for now, but anyone who isn't already following the shows on Twitter might want to start now.