An industrial fire in Shelton, Washington released toxic smoke into already unhealthy air Wednesday night. Mason County Search and Rescue advised residents within a half-mile of the fire to shelter in place, close all windows, and turn off air conditioning until further notice.

The fire started in the 1000 block of State Route 3. The highway closed south of Shelton for several hours during the firefight. SR 3 reopened around 1:30 a.m. Thursday.

The fire spread to a wooded area north of the building that caught fire. Firefighters said the blaze was under control around 10:20 p.m., but was expected to smolder for several hours.

The North Mason Professional Firefighters union joined the firefight, along with crews across Mason and Thurston counties. The Washington Department of Ecology also responded and monitored air quality.

The cause of the fire is currently unknown.

Check back here for developments as they unfold.