As weird and concerning as they appear, the virus that causes the dark, wart-like horns or tentacles to grow on cottontail rabbits is relatively common and usually not anything to worry about.

The unusual appearance of the rabbits has drawn significant concern among locals and even social media users online.

Northern Colorado—specifically a town called Fort Collins—has recently made headlines for its rabbit population after it was revealed that several of them had long black tentacles growing all over their bodies.