Washington state Transportation Department officials say a large mud and rock slide has shut down more than 30 miles of U.S. Highway 12 between White Pass and the intersection with State Highway 410.
Mud and tree debris reportedly blocked both lanes Wednesday afternoon along a swath of highway 40 yards long.
No injuries have been reported.
Highway officials say a detour is available via Highway 410. Local traffic is allowed closer to the rockslide to access other roads in the vicinity.
The road is closed in both directions between milepost 151 and milepost 183.WSDOT expected to re-open the highway around 11 p.m. Wednesday.