GREAT FALLS — A grizzly bear and her two cubs are being relocated after killing about 10 sheep near Lake Frances in north-central Montana.

The bears were to be released Friday in the area of the North Fork of the Flathead River.

Grizzly bear management biologist Mike Madel said the bear family had been spotted near the east shore of Lake Frances.

According to the Great Falls Tribune, the grizzlies came upon an unprotected band of sheep owned by Don Sporleder and kept coming back, killing around 10 of them, Madel said.

Initial efforts to trap the bears were unsuccessful.

Madel darted the adult female, named Pondera, from a helicopter Wednesday. The bear ended up in the river, where Madel and ranchers had to scramble to keep her from going under.

“I had to jump in the river and hold her head up,” Madel told the  Tribune. “But one great thing about her going in the river is that her body was kept cool.”

Bears can be at risk of overheating, he said.

Madel was later able to dart the two 7-month-old cubs, Messenger and Williams.

Madel said the bears were thinner than they should be. Pondera, estimated to be 6 years old, weighed 325 pounds. The cubs weighed 51 and 60 pounds.

The mother has been radio-collared and all three grizzlies have been outfitted with ear tags so wildlife officials can track them.