The 16-year-old is recovering after waking up in a nightmare.
A black bear attacked the girl while she was just feet away from her family in Great Smoky Mountains National Park.
"This bear was exhibiting predatory behavior it attacked in the middle of the night with no known provocation," said Dana Soehn, with the Great Smoky Mountains National Park.
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Despite injuries to her head and an incredible amount of blood loss, officials say the girl was conscious throughout the attack.
"Fortunately, the family was close by and able to scare the bear away and keep it at bay until the Rangers arrived," Soehn said.
Their back country campsite was nearly six miles from the trailhead in very steep terrain with thick foliage. The Tennessee National Guard had to perform an emergency evacuation mission by helicopter.
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"We actually had to do the hoist rescue into a very tight space had to drop the medic down through a small hole in the trees... that can be a pretty intense operation."
After the attack, two bears were spotted in the area. Officials say one larger male repeatedly tried to enter the campsite despite attempts to scare it off. Rangers shot and killed the bear the family identified as the one responsible for the attack.
Park officials said the family of five properly secured their backpacks and food as visitors are instructed to do and, in the face of danger, responded appropriately to the bear attack.
"If a bear continues to approach you, or it shows aggressive behavior as in this situation, we encourage everyone to fight back," Soehn said. "Do everything they can to discourage that behavior. And in this incident, the family was successfully able to thwart that bear from any more serious attack."
This comes just days after a woman in Alaska was chased off a hiking trail by a group of grizzly bears. She fended them off with bear spray but it took 40 hours for her to find her way back to safety.
As National Parks across the country are flooded with guests, encounters with bears are on the rise but attacks are still rare. Black bears are the most common in North America.