13 Bison Dead After Semitruck Crashes Into The Animals Outside Of Yellowstone National Park

A herd of bison races across a bridge in Yellowstone National Park, Wyoming.

Thirteen bison were killed Wednesday when a tractor and trailer ran over the animals near Yellowstone National Park, officials said.

The incident occurred on Highway 191 near mile marker 4 in southern Montana, the West Yellowstone Police Department said in a statement Friday. The area is close to the western entrance to the national park. Authorities said the semi-trailer hit all the bison, and some of them were euthanized "due to serious injuries."

Bison walk along the edge of Yellowstone National Park on March 17, 2011 in Gardiner, Montana.

Officials say bison are often found near roads and trails during the winter months because they can move more easily and potentially interfere with vehicles.

Start your day smarter. Get all the news you need in your inbox every morning.

"Due to the abundance of wildlife in our area and our proximity to Yellowstone National Park, we regularly encounter injured and killed wildlife on our area's roads," the department said. "We are always saddened by each of these incidents, especially when so many animals are lost."

READ ALSO: 1 killed, 9 injured in shooting near New Year's Eve party in Alabama

What's everyone talking about?: Subscribe to our newsletter to get the latest news of the day.

Police used the incident to remind people to slow down on certain roads and in certain weather conditions, noting that it is difficult to stop on icy roads. Road conditions at the time of the crash "require driving below the posted speed limit". Temperatures in West Yellowstone were below freezing at the time of the crash, according to the Weather Underground.

Authorities initially thought multiple vehicles were involved in the bison's death, but determined that the other two incidents were isolated incidents.

Bison, the largest land mammal in North America, have made Yellowstone their home since prehistoric times, according to the national park. The species was endangered by hunting in the 19th century before being protected by the US military. According to official statistics, about 5,450 bison live in the region in the summer of 2021. You can often see herds of animals.

Police said the Montana State Patrol is investigating the incident. USA TODAY has reached out to the Montana Highway Patrol and the National Park Service for comment.

Follow Jordan Mendoza on Twitter: @jordan_mendoza5.

This article first appeared in USA Today: 13 bison died after a tractor-trailer crashed into a herd outside Yellowstone National Park.