IOWA CITY, Iowa (AP) — The University of Iowa’s department of public safety had some fun on social media at the expense of its Iowa State counterparts.

The undefeated Hawkeyes and winless Cyclones will square off in their annual rivalry game on Saturday, the third game of the season. So Iowa police used their verified Twitter account Tuesday to tweet a knock-knock joke Iowa State’s way.

Iowa State police replied “Dare we ask ‘who’s there?'”

Iowa police responded with a picture of coaches Kirk Ferentz and Paul Rhoads sharing a laugh.

The caption read “Owen. Owen Who? 0-2.”

Iowa State police acknowledged the burn, tweeting back “You’ve won this time … “

Iowa safety director Chuck Green says the jokes were meant to be a fun way to promote the game.

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