By John Annese, Tribune News Service

Troy Warren for CNT

A frustrated substitute teacher in New York threatened to shoot up a classroom full of middle school students, then voluntarily confessed what he said to school officials, police said.

Alejandro Rocha, 52, was teaching an art class Wednesday at Intermediate School 5, the Walter Crowley School, in Maspeth Queens, when he became angry at the class.

“If you won’t do as you’re told, I’m gonna shoot you — and yes, I have a gun,” he told the nine kids, all between ages 11 and 12, sources said.

None of the children made a complaint about his threat.

Instead, Rocha told on himself.

He volunteered what he said to a supervisor, said it was a bad joke and that he was sorry, sources said.

The apology landed him in cuffs. Police charged him Wednesday night with making a terrorist threat.

Rocha, who lives in Sunnyside, was awaiting arraignment in Queens Criminal Court.

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