Grizzly in Montana attacks was underweight, but still no clear answer why she mauled 3 campers

Wildlife officials say a grizzly bear that preyed on campers outside Yellowstone National Park was underweight, but it was in an area with ample food supplies and did not appear to be starving.

Montana officials said Monday that a necropsy has been completed on the female grizzly. The results are being analyzed.

Female grizzlies typically weigh 300 to 400 pounds, but the attacking bear weighed 221 pounds. Her three cubs also were underweight.

Grizzly expert Chris Servheen with the U.S. Fish and Wildlife Service says the bears' weight alone does not explain Wednesday's attacks.

One person was killed and two others were injured in the attacks at the Soda Butte Campground.

That campground remains closed, but authorities have re-opened two others that were shut after the attacks.