Mark Conrad, the superintendent of schools in Nashua, N.H., got the chilling news last Sunday morning. An email sent to a school board member threatened a lethal attack on multiple schools, naming the sites, how students would be harmed and the date, Dec. 21 — the next day.
“It was a first for us, in terms of the breadth of the threat and the specificity,” Mr. Conrad said. On Sunday evening, after consulting with the police, Mr. Conrad did something that, as far as officials in Nashua knew, had never been done there before: He ordered that all schools stay closed that Monday because of the fear of violence.
