Delaware legislators in Washington sent a letter to FBI Director James B. Comey Wednesday requesting answers on when and how the federal agency gets involved in helping to investigate school bomb threats.

The letter was signed by Sen. Tom Carper, Sen. Chris Coons and Rep. John Carney.

Citing recent bomb threats made at schools up and down Delaware, the legislators pointed out that the threats of violence were also affecting schools in California, New Hampshire and elsewhere.

“As we understand, bomb threats of this nature are viewed as criminal acts to be handled by state and local law enforcement. With that said, when a bomb threat seemingly replicates itself across multiple schools, school districts, and states—as the Delaware threats did— it may be appropriate to bring federal resources to bear, too, in order to identify the sources of the threats and to prevent future incidents from occurring,” members of the Delaware delegation stated in their letter.

The legislators want the FBI director to answer five questions including under what circumstances does the federal agency assist state and local law enforcement entities with investigations into threats of violence against schools. Also, if the FBI provides guidance or training to state and local law enforcement related to best practices for addressing threats of violence against schools.

The legislators want to know if the FBI maintains statistics regarding school threats, and if it works with other federal partners, including the Bureau of Alcohol, Tobacco, Firearms and Explosives, to address threats of violence against schools.

The last question asked if the types of technologies used to make threats of violence against schools, including social media or computer-generated phone calls, make it more difficult to evaluate the credibility of a threat.

The legislators didn’t include a set date for the FBI's response.

So far, the investigation into the bomb threats in Delaware has been handled by state police and other local law enforcement.

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