TUCSON (Reuters) - Arizona drivers were warned of the undead roaming a desert highway near Tucson over the weekend, after a suspected prankster tampered with an electronic road sign, police and news media said.

Someone without a good grasp of spelling reprogrammed a digital road sign on a highway near Marana, northwest of Tucson, to read “Caaution Zombies ahead!,” the Arizona Daily Star newspaper reported on Monday.

Marana Police Department said it appeared to be a practical joke.

“We didn’t get any complaints or any other problems in the area... (and) no reports of zombies,” Sergeant Chris Warren told Reuters.

“Sometimes those boxes are just left open and if somebody knows how to do it they can just go over to it, open it up and just start typing.”