A power outage has forced a shutdown of the Highway 99 tunnel through downtown Seattle on Thursday morning, Washington State Department of Transportation said on X.

WSDOT first posted about the outage shortly before 7:40 a.m. The agency said the tunnel remains closed as of 8:20 a.m. Thursday. Both directions are affected.

“There is no estimate for power restoring/the tunnel reopening. Seek alternate routes and plan for added travel time,” WSDOT said on X.

This story is developing. Check back for updates.

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