A hunter tracking a mountain lion in Idaho stumbled upon a bizarre deformity that has baffled fish and game officials.

The male lion was killed by an Idaho resident who tracked the animal after it attacked his dog. But the hunter – and game authorities – were taken aback by a fully formed set of teeth growing out of the predator’s forehead.

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Local wildlife officials said they’d not seen such a site before, but they did have several suggestions for the cause of the strange growth.

The extra teeth could have come from a conjoined twin that was absorbed into the fetus, or it could have been a “teratoma” tumor, which contains tissue from which teeth, hair or even fingers and toes can develop, said the Idaho Fish and Game Department.

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The hunter notified fish and game authorities and an officer verified his hunting license and documented the mountain lion’s death.

The animals prey usually prey on deer, elk, moose, mountain goats and deer. But when snow is deep and temperatures are low, the lions sometimes prey on domesticated pets and livestock.

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