A plot to attack a school with explosives by a former student has been foiled in Tampa in the US state of Florida, police said.
Writings about the alleged plot and dangerous materials have been seized, Tampa Police chief Jane Castor was quoted as saying by Xinhua.
A 17-year-old boy, Jared Michael Cano, was arrested after police got a tip-off from an anonymous caller. Reports said the student planned to kill at least 32 people, including two principals at the Freedom High School.
POlice said they found a manifesto with Cano's minute-to-minute plan for the massacre, detailing each murder he intended to commit.
Cano has been charged with threatening to throw, project, place or discharge a destructive device. He also faces charges for possession of bomb-making materials, cultivation of marijuana, possession of drug paraphernalia and possession of marijuana, police said.