Students and parents are only now learning the details of what sheriff's officials in Florida called a "credible" and "dangerous" threat by two classmates who planned to steal an arsenal of weapons and shoot classmates — some of them at random and others on a hit list — more than a month ago.

The two boys — who, at ages 15 and 16, weren't identified because they're juveniles — have been involuntarily committed even though Orange County sheriff's detectives recommended that they be charged with conspiracy to commit murder at Timber Creek High School in Orlando, NBC station WESH reported.

The sheriff's office said the threat was posted on Facebook and that authorities learned the specifics from one of the conspirators, who apparently lost his nerve. It said weapons were found in both boys' homes.

Until the heavily edited investigative report was released over the weekend, all that parents had heard of the plot was a recorded message Jan. 14 from the school's principal that said a student had made threats online and that the threat had been foiled by another student, WESH reported.

School officials couldn't immediately be reached for comment Monday because the system was observing the Presidents Day holiday.

According to the sheriff's report, the suspects confided in each other that they both heard voices, cut themselves and shared an interest in the violent video game "Call of Duty."

Authorities said one of the boys planned to steal his father's semiautomatic rifle and pistol, The Orlando Sentinel reported. With his accomplice, they planned to open fire on a specific group of students and then on other students at random.

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Orange County School Board Chairman Bill Sublette told the Sentinel that the case was "very, very serious," saying it was rare for mentally ill students to go so far as to draw up a hit list. 

Amanda K. Janner, a clinical psychologist in winter Park, Fla., who has successfully treated violent teenagers, agreed that the students' hallucinations, specific date and established access to weapons required an immediate response.

When more than one child is involved, "it certainly does build on itself," she said. "It almost reinforces their beliefs, their thoughts, when somebody else shares that. It normalizes it."

Classes resume Tuesday at Timber Creek. The school district told WESH it plans no special security measures.

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