KEARNS, Utah (AP) — Police say a 17-year-old boy will face felony charges for saying on Twitter that he was going to blow up Kearns High School.

Unified Police Lt. Justin Hoyal says a caller who was apparently from Washington, D.C. reported the Twitter post about 9 a.m. Thursday. Hoyal says school police checking it out found a photo of explosives attached, and put the school on lockdown.

Officials say the student wasn’t at school that day, but they found him a short time later.

The teen told police the post was just a joke.

Hoyal says it didn’t appear the student was planning to carry out the threat, but adds that police take such statements seriously.

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