A man approached a pack of wolves in Yellowstone National Park as visitors watched in horror from far away. Keith Allen Kerbs, who took video of the man, was taking pictures of the five black wolves when the man walked toward the animals. At one point, he was spraying bear spray at the wolves, and eventually managed to escape. The National Park Service said there have been no reports of wolves attacking humans in Yellowstone, but has still advised visitors not to approach them. | CBS News