Some cottontail rabbits in Fort Collins, Colorado, have been drawing attention because they have wart-like growths on their faces that look like horns.

Wild rabbits with strange black growths on their heads have caused concern among Colorado residents with some referring to them as “Frankenstein” rabbits.

Viral photos have inspired a fluffle of unflattering nicknames, including "Frankenstein bunnies," "demon rabbits" and "zombie rabbits."