Shope papillomavirus, a common and naturally occurring virus in wild rabbits that causes wart-like growths which can resemble horns or even tentacles.Though the appearance of these animals is startling,

The rabbits – also nicknamed “Frankenstein bunnies” – with their bizarre “horns” were once the stuff of ancient folklore.

Unusual-looking rabbits have recently been spotted in Washington, sporting wart-like growths that can resemble horns.

Wildlife officials in Colorado are monitoring an unusual increase in cases of Shope papillomavirus, a disease affecting wild and domestic rabbits, following a higher number of sightings this summer.

Experts and local officials have issued a warning to anyone who encounters a 'zombie rabbit' on their travels. People have been left concerned after spotting the poor bunnies in Fort Collins, Colorado, with strange, gnarled black growths sticking out of their face and neck.

It's the cottontail papilloma virus (CRPV) at work - giving rise to the 'jackalope' myth (rabbit with antlers) in modern times - which causes benign, Lovecraftian tumours to materialise on the head of the animals.