One day this past April, schools in more than a dozen cities and towns in Massachusetts received bomb threats, triggering evacuations, searches by the bomb squad and the assignment of extra police officers. Three days later, 32 schools received bomb threats, prompting a similar response.
On both days, school was interrupted for students, and police, fire and other public safety officials had to shell out personnel and other resources to respond to the hoaxes.
Officials across the country say school threats, including but not limited to bomb threats, are increasing. One estimate is that during the last school year there were about eight bomb threats per school day. And that estimate doesn't include other threats of violence or disruption.
Massachusetts had 135 bomb threats in the 2015-16 school year, the most in the country, according to a tally based on media reports by the Educator's School Safety Network.
Sgt. William Qualls, commander of the state police bomb squad, said he believes the number was even higher.
"They are extremely frustrating, especially when a school gets multiple threats over a short period of time. Not only are you dealing with students and first responders, but also the parents. The entire community is affected," Qualls said.
Two years ago, public safety officials began training school administrators to do threat assessments to determine how they should respond. Depending on the type of threat and whether it has been called in to multiple schools, officials decide whether to evacuate and call in the bomb squad or to shelter in place and do a more limited search.
"We take each threat very seriously until we have reason to believe that it's not a serious threat," said Jennifer Mieth, a spokeswoman for the state's Department of Fire Services.
Many of the threats during the 2015-2016 year were made to multiple schools through robocalls, including the two threats in April.