"Panda-monium" swept through a northern Arizona city courtesy of a street sign hacker who warned motorists of a "ROGUE PANDA ON RAMPAGE."

State transportation officials said someone was able to post the hoax warning by hacking into an electronic message board in Flagstaff, Ariz., last weekend, Reuters reported.

"Someone had to know what they were doing to go in and change the message," said Mackenzie Kirby, an Arizona Department of Transportation spokeswoman. "It's not easy."

Kirby joked there had been no sightings of rogue pandas, though she's been sent several photoshopped images via email of the cute creatures getting ready to rumble.