Two non-fatal bear attacks took place Thursday in Yellowstone National Park, officials reported.
According to ABC News, one attack took place just west of Island Park Reservoir in Idaho when a bear charged two private contractors engaged in habitat assessment work and unaware of the bear sleeping behind a nearby tree.
The bear bit one of the men in the thigh and backside, Gregg Losinski of Idaho Fish and Game told the news outlet. The other man attempted to spray the bear as it charged him, but was unsuccessful in warding off the animal which attacked both of the man's hands.
The second attack took place on Cygnet Lakes Trail in Wyoming when a bear cub approached a group of four hikers prompted a nearby sow to charge.
Two of the hikers received bite and claw wounds while the others scared the bears off with bear spray.
"They were following all the directions that we encourage people to do when they're in the back country, which is hike in groups, carry pepper spray and make noise on the trail," Yellowstone spokesman Dan Hottle told ABC News radio. "Unfortunately, a mother with cubs in the park is the most dangerous animal we have."
All four were able to walk out of the trailhead at which point one received treatment at the scene while the second was transported to a nearby hospital for treatment.
"The biggest worry is infection, as bears do not have clean teeth," Loskinski explained.
According to Reuters, no action is planned against the mother bear on the grounds that her actions were driven by a natural defensiveness for her cub.
Historically, bear attacks in Yellowstone National Park are rare: between 1980 and 2011 there were only three grizzly bear-caused human injuries in developed areas and 32 in the "backcountry." And while 2011 marked a deadly year after two were killed in grizzly bear attacks, the last fatal bear attack to take place in the park prior to that year was in 1986.