A visitor captures the moment an angry bison charges a group of tourists at Yellowstone National Park in the U.S. The kids and their relatives get very close to the animal. They wanted to take pictures and video, but don't realize the bison is getting agitated and ready to attack. All of the sudden the bison runs after a kid who barely escapes. Nobody is injured. Bisons are known for protecting their space in the wild. The video was filmed in 2012.