Students who attended Sandy Hook Elementary School in Newtown, Conn., returned to class this week at a different school, and under heightened security.

Families arriving at the former Chalk Hill Middle School, in the neighboring town of Monroe, were met Thursday by police officers who checked parents’ IDs. The parents, who were invited to stay with their children, later reported seeing officers around the school.

“I think right now it has to be the safest school in America,” Monroe police Lt. Keith White said.