UPDATE: 8:15 p.m.

Firefighters have released additional details in the fire, including that the building was full of propane tanks and ammo. Read the full story here. 

UPDATE - 4:15 p.m.: 

Natrona County Sheriff's Office Investigations Sgt. Taylor Courtney said the highway has reopened aside from a service road to the south of US 20/26 near the building. 

An industrial fire has been reported at 5715 West Yellowstone in the Mills area.

U.S. Highway 20/26 is blocked.

Casper Fire-EMS Deputy Chief Jason Speiser said a shop caught fire.

All the occupants were evacuated safely. There are some vehicles inside the building

The fire apparently has spread to the surrounding area, but fire crews are getting it under control, Speiser said.

Please avoid the area.

This story will be updated.

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