Rafael Loera, 56, and Maribel Loera, 50, were arrested on charges of concealing human body parts and child abuse after firefighters responded to a fire at their home and discovered the remains in the attic.
Hours earlier, social workers from the Arizona Department of Child Safety removed two children -- ages 9 and 4 -- from the house. A week before, an 11-year-old, who called Phoenix police to say she was home alone, was removed by social services when they suspected child abuse.
A district spokesman told the Arizona Republic that Loera had worked at Sierra Linda High School in Phoenix.
The district sent a letter to parents Wednesday that read: "Sierra Linda High School is committed to the safety and security of our students and staff. Therefore, it is imperative that we share the following information. We want to make you aware of the arrest of an employee on serious allegations that has already been shared via media outlets. The alleged crimes did not occur at Sierra Linda High School and the staff member will not return to the school. Of course, we are very troubled by this incident."
The letter didn’t mention Loera by name but the district confirmed to the Arizona Republic it was referring to him.
Fox News' Vandana Rambaran contributed to this report.