SALEM — A fire in the flue of a piece of equipment Wednesday morning resulted in a passerby calling 911 to report seeing the roof of the Radiac Abrasive plant in Salem on fire.

The call was made around 9:44 Wednesday morning with the caller reporting it didn’t appear anyone was evacuating the building.

As emergency officials worked to contact people at Radiac, others responded to the call, with Salem police officers arriving at the scene first and reporting a considerable amount of smoke coming from the building.

Ultimately workers were evacuated as firefighters worked to determine the cause and extent of the fire, which was eventually determined to have been from soot in a flue from one of the machines used at the plant.

Reports indicate employees had started diagnostic testing on the machine when the flue fire started.