PUEBLO, Colo. (CBS4) – Colorado transportation officials aren’t laughing about the silly messages someone has been posting on some roadside safety signs in southern Colorado.

The text has showed up on the electronic signs in recent days in the Colorado Springs and Pueblo area, and have included warnings about vampires and aliens. CBS4 obtained images of the signs carrying the following messages:

– Caution: Zombies Ahead!!!

– Sorry Mario The Princess Is In Another Castle

– Rapture Ahead

The computer system behind the signs is complex and difficult to operate even for those who are trained on it, according to Rick Bowman, a contractor for the Colorado Department of Transportation.

Bowman, vice presidet of A-1 Barricade & Sign, told KRDO-TV in Pueblo that “most of our people have to sit and read the manual, sometimes before they change the sign to make sure they are doing it right.”

Bowman said whoever is responsible, whether it’s a teenager or someone who has insider knowledge of how the system works, should realize that they are putting drivers in a potentially deadly situation.

Bowman is a representative for the American Traffic Safety Services Association and says that because motorists aren’t seeing the messages they are supposed to there’s a “real safety hazard” going on.

Officials want anyone who sees a roadside safety sign with an appropriate message on it to contact authorities right away. They also say that drivers who see one of these messages should drive extremely carefully in the area because they might be missing an important notification.