Fire forces Union Middle School to cancel classes for a second day.

An electrical fire early Thursday morning forced a Sandy middle school to cancel classes and activities for two days.The fire damage at Union Middle School was not extensive, Canyons School District officials wrote in a statement early Thursday, but fire authorities had not yet confirmed the building was safe.“The chief concern at this point is making sure the building is free of any smoke and carbon monoxide that may have accumulated,” district officials wrote.Officials initially pl