According to a federal complaint, 32-year-old Joseph Taylor McKeel was arrested Wednesday morning on his way to Independence High School.
Authorities say he was found in possession of a thumb drive with 150 images of child sexual abuse as well as a meth pipe.
Police overseas in Scotland say they first spotted McKeel trading the images on a social media app called Telegram and alerted the FBI.
McKeel appeared in federal court in Downtown Brooklyn, where he was ordered held without bail.
A judge is expected to decide whether he will be placed in a drug treatment program. His attorney told the court he struggles with addiction.
McKeel, who teaches at-risk students, has been suspended from his position.
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