Tampering with road signs is illegal and those who are caught doing so will face charges, even if they are trying to warn people of an impending zombie apocalypse.
Pranksters in Maine, USA, hacked an electronic road sign which originally warned drivers of roadworks ahead.
The sign was changed from reading "Night work 8 pm-6 am. Expect delays" to "Warning Zombies Ahead!"
Nicole Clegg, a spokeswoman for the city of Portland, was not amused by the prank. "They're not a toy," she said, speaking about the signs.
She added: "I now have to talk to a New York radio station about why we shouldn't be alerting the public to zombies."
If the perpetrator is caught, they could be charged with a misdemeanour and face up to a year in jail and a $1,000 fine.
Critics of sign prank get a rise out of fans of the walking dead (Portland Press herald)