An avalanche spilled over part of Interstate 90 Wednesday afternoon near St. Regis, according to the Montana Department of Transportation.
Officials have closed the westbound lanes of traffic and will soon begin rerouting drivers to Highway 135, according to Montana Highway Patrol.
The slide comes in the middle of a week plagued by rollovers, semi-truck crashes and subsequent injuries along the I-90 corridor due to heavy snow and slick roadways.
When reached by phone, a woman at the MDT office said there was no time for updates.
"We're so swamped around here," she said.
Montana Highway Patrol Capt. Jim Kitchin said no vehicles were caught in the avalanche, and that MHP would soon be assisting MDT in rerouting traffic up MT Highway 135 to Highway 200. Even that option, he said, sounded a little treacherous.
"Pretty sure they're getting a lot of snow on 200 right now," he said. "There's a lot of crashes and we're getting a lot of calls."
Kitchin said the avalanche was relatively small, but due to conditions, officials decided to close the road down until further notice.