A grizzly boar that charged out of the woods towards Yellowstone visitors was hazed back into the woods by a ranger/Jay Dawg via YouTube

A Yellowstone National Park ranger averted potential tragedy by firing rubber bullets and "cracker shells" to stop a grizzly that charged onlookers who failed to maintain a safe distance from the bear. 

A video of the incident captured by Jay Dawg shows the ranger trying to stop traffic and get onlookers hoping to capture a photograph of a pair of grizzlies to move away.

When the grizzly boar bounded out of the woods between Norris Junction and Swan Lake Flat and rose up on its hind legs to look around at the people, the ranger darted back to his truck, pulled a shotgun, shouted at the bear, and fired a few rounds in its direction to get the bruin to reverse course and head back into the woods.

The ranger resorted to firing rubber bullets and "cracker shells" at the bear/Jay Dawg via YouTube

The incident last Friday night came the same day that a lone hiker was attacked by another grizzly on the Beaver Ponds Trail near Mammoth Hot Springs.

"We've already seen numerous close calls with bears this year, and had one visitor seriously injured last week," Yellowstone Superintendent Cam Sholly told the Traveler on Wednesday. "Visitors need to maintain appropriate distances to wildlife and understand these animals are wild and can kill or injure humans very easily if threatened.

"The resource management technician in the video did an excellent job of hazing the aggressive bear away from visitors who obviously had no clue what kind of danger they were in," the superintendent added. "His actions likely saved lives. Non-lethal bean bags and rubber bullets were used in this situation, and are some of the tools we use to haze wildlife away from visitors."

Park regulations call for visitors to remain at least 100 yards away from bears, but in this case some were within 20 yards, according to park staff.