COLORADO SPRINGS, Colo. (CBS4) — Drivers in Colorado Springs got an unexpected warning over the weekend. Someone got into an unlocked message sign and changed it to read “Use caution… Zombies ahead.”

(CBS)

It was supposed to state “Dublin closed ahead.”

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Officials with Colorado Springs Utilities say the prank was a learning opportunity for the agency.

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“It was definitely a way for us to see how we can do processes better on our side working with our contractors making sure that all of those variable message signs are locked to make sure this doesn’t happen again.”

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Springs Utilities heard there could be another sign that was changed out there and they’re trying to track it down.