A hunter tracking down a male mountain lion discovered that the animal had a deformity on its forehead which wildlife officials describe as an abnormal growth of teeth, hair and whiskers. The lion was legally killed on the same day it attacked a dog on the hunter's property near Preston, Idaho.

On. Dec. 30, 2015, the lion was seen attacking a dog in the Weston area. It retreated to the hills where a hunter, who was not named, began following it within three hours of the attack. The lion was successfully tracked and killed using hounds, while the dog was fortunate to have survived the attack with only puncture wounds.

The Fish and Game Department in Idaho released a photo of the deformed mountain lion and issued a statement sharing additional information and a few facts about the animal. The photo shows that the lion had another set of fully formed teeth and whiskers that grew out of the top of its head. Wildlife officers claimed that they've never seen anything like it in the past, triggering a lot of theories on the lion's condition.

"A hunter brought it in, and there was something extra. We haven't seen anything like this in our region," Jennifer Jackson, Idaho Fish and Game Region 5 spokeswoman said.

The department could not exactly explain the nature of the abnormality. Officials speculated that the teeth and whiskers could be the remains of a conjoined twin that died or stopped developing while they were still in the womb. It must have embedded itself on its twin lion.

Another theory that could explain the deformity, officials added, could be a growth of a teratoma, a rare tumor that arises during the development of a fetus. The department said these types of tumors contain tissue from which extremeties like fingers, toes, teeth and hair develop. Teratoma can be found both in animals and, in extremely rare cases, in humans.

Further analysis of the male mountain lion will take place after the hunter has reported the harvest to the Fish and Game Department. This involves a process of verifying the hunters valid hunting license as well as documenting information on the method and location of harvest and information on the animal itself.

The mountain lion or cougar (Puma concolor) is common in Idaho and in the northern parts of the United States, mostly in mountainous areas with cliffs and rimrock. It has a yellowish color with some reddish spots on its back. The feline commonly relies on mule deer, which comprises about 75 percent of its diet throughout the year. Other prey include moose, mountain goats, raccoons, rabbits and other small animals.