Remains of grizzly bear later found decapitated and declawed in Montana

Wildlife officials are investigating an incident where remains of a grizzly bear were later found decapitated and declawed in the Yellowstone River north of Gardiner, Montana, last month.

Montana Fish, Wildlife and Parks officials discovered the 25-year-old male bear when it washed ashore an area along the river on June 10. Plans were made to remove the remains via boat or helicopter the next morning.

But when officials returned the next day, someone had removed the bear's head and claws that night.

“It makes no difference if a person poaches a bear to kill it or to take its hide and claws as trophies or comes upon a dead grizzly and decides to help themselves to the parts. Grizzlies are a federally protected species, and it’s illegal," Kevin Frey, senior grizzly specialist with Montana Fish Wildlife and Parks, told the Mountain Journal.

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According to the National Park Service, there are protections for grizzly bears within the Greater Yellowstone Ecosystem under the Endangered Species Act. This bear resided in the park and was tagged with the number 394, according to Billings Gazette.

Frey said it is possible the bear could have drowned.

"With the bear being 25 years old, you know, bears are like people. They get old and arthritic and sore. I'm not sure if this one was but bottom line is that they're not at their prime athletic age anymore and they could succumb to high water," Frey told USA Today.

U.S. Fish and Wildlife Service authorities also are investigating.

This article originally appeared on USA TODAY: Grizzly bear found decapitated and declawed in Yellowstone River