Highway 12 was closed Wednesday for a 32-mile stretch from the Oak Creek Feeding Station west to the White Pass summit, according to the state Department of Transportation.
The cause was a large mudslide five miles east of the Rimrock Tunnel. DOT had no estimate as to when the highway will reopen.
Drivers were advised to take a detour over Chinook Pass using Highway 410. For current traveler information, visit www.wsdot.wa.gov/traffic or call 5-1-1.