The ranking Democrat on the House Select Committee on Intelligence says the threat that shut down the Los Angeles school system is believed to be a hoax.
U.S. Rep. Adam Schiff, D-Calif., said a preliminary investigation indicates that the threats in Los Angeles and New York City were designed to disrupt school districts in large cities.
He says in a statement Tuesday that investigators are still gathering information about the origin of the threats.
Officials have said the threats targeted students and involved gun attacks and explosive devices. It led Los Angeles school officials to close more than 900 public schools and 187 charter schools.
New York City officials say they received the same threat as Los Angeles but quickly concluded it was a hoax.
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