The hunters were attacked by a bear in the Gravelley Mountains, southwest of the US city of Bozeman, on Monday, the Montana Fish, Wildlife and Parks agency confirmed. It is not known if the same bear was involved in both the attacks. All three of the men were left with “moderate to severe” injuries.
The bear charged at two men during the first attack while they were hunting in the mountain range at 7.30am.
One of the men sprayed the grizzly with bear spray while it was “on top of” the other man and it went away.
They were treated at a hospital in the small town of Ennis.
Later in the day, they then visited an outdoors shop to buy new clothes and relayed their tale.
A worker at the shop told NBC Montana: “They said he was up and in their face, just right there on them before they even had a chance to really even grab a gun or do anything, which I think is important for people to know.
“The bear was on top of one of the men, and the other one was able to get to his bear spray.
“He sprayed the bear, and that’s what made the bear leave.”
The third man was attacked later in the day at 6.30pm.
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Both attacks are still being investigated, Montana Fish, Wildlife and Parks said.
Wildlife authorities often capture and kill bears that become too comfortable being around people.
In rare instances when people are attacked, the animals are also killed.
Officials are now urging people to be careful and carry bear spray during seasons of spring, summer and autumn.
Yellowstone National Park has a population of grizzly bears, including in the Gravelly Mountains.
During the mid-1970s, there were around 136 bears.
But now there are around 700.
Last year, a hunting guide in northwestern Wyoming was mauled to death by a bear and its cub.