Frightening sightings of mutated rabbits with tentacle-like growths jutting from their heads and necks are on the rise in Colorado — and are popping up in other states, too, as the Frankenbunnies begin hopping across the country, according to 9NEWS Northern Colorado.

As the virus spreads, turning cute cottontails into horned monsters, fears of a national wildlife crisis are also on the rise.

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One horrified Fort Collins, Colo., resident described a rabbit she saw as having “black quills or black toothpicks sticking out all around his or her mouth.”

“I thought he would die off during the winter, but he didn’t,” says Susan Mansfield. “He came back a second year, and it grew.”

Colorado Parks and Wildlife says it has received more than a dozen reports of the floppy-eared freaks.

And though wildlife experts say the disease cannot jump to people or other pets, such as cats and dogs, they are warning folks to steer clear of the bizarre bunnies, which they say have been infected by the cottontail rabbit papillomavirus (CRPV), also known as Shope papillomavirus. The disease causes them to sprout tumors made of keratin, the same protein that makes up human hair and nails.

Usually, the illness passes, experts say, although in some cases the tumors turn cancerous or grow so big that the quivering creatures can no longer munch their food.

“Typically [they] become infected in the warmer months of summer when transmitted by being bitten by insects like fleas and ticks,” says Colorado Parks and Wildlife’s Kara Van Hoose, per the Coloradoan.

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Infected rabbits have now been seen near St. Paul and Minneapolis and could soon scamper throughout the Midwest.

“My neighborhood is filled with cottontails with Shope papillomavirus,” posts one St. Paul resident.

“Same in Minneapolis. By mid-late summer it seems all the surviving new rabbits have it,” echoes another.

Cases of the illness were first noted by hunters in Iowa and Kansas in the 1930s, and could have fostered the myth of the horned jackalope, according to the Smithsonian.

One dog owner from the Northeast tells the Enquirer he’s afraid to take his pooch on long walks.

“I don’t care what they say about the virus not jumping between species,” says Allen Serrano, the owner of a 4-year-old Cavachon named Lily. “Those rabbits are terrifying!”