BALTIMORE (AP) — Authorities say a Maryland teenager has been arrested and charged with threatening mass violence.

Montgomery County police have identified the teen as Luis Amilcar Cabrera, a former student of Bethesda’s Walter Johnson High School. He’s 18 and was being held without bond.

A Saturday police statement says Cabrera posted a photo on social media showing him holding an AR-15 rifle with the words:

“School shooter.” Police say several students have also reported that Cabrera has posted messages about hating the school and threats to “shoot up” the place.

Detectives obtained a warrant for Cabrera’s arrest, citing threats and recent photographs. He was charged on Friday.

It wasn’t immediately clear if Cabrera had a lawyer. Calls made to what appeared to be his family’s Rockville address went unanswered.

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