An elementary school teacher has been placed on administrative leave after police said they found thousands of files containing child sex abuse material in his possession.

Pleasantview Elementary teacher Martin Waskowski was arrested on Wednesday in Vermont after Border Patrol agents identified him as a suspect at the Highland port of entry.

One device contained more than 12,000 files appearing to be child sex abuse material, according to a preliminary review.

Waskowski was re-entering the U.S. from Canada when he was nabbed in a records check by law enforcement, according to a federal complaint.

A search of his cell phone allegedly revealed images and videos of adult men committing sexual acts with prepubescent boys.

Michigan State Police then searched his home, where they confiscated computers, hard drives, and an iPad.

One device contained more than 12,000 files appearing to be child sex abuse material, according to a preliminary review.

Waskowski had been a teacher at the elementary school in Eastpointe for three years and had been a long-term substitute as well.

He allegedly confessed to police that he had collected the child sex abuse material for approximately 20 years, and said that he knew the behavior was wrong, had tried to stop, but had not sought treatment to stop.

He was charged with possession and transportation of child exploitation materials. He was released under supervision and location monitoring.

District officials said they put him on administrative leave pending the outcome of the investigation.

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"Prior to this formal notification, the District had no knowledge of, nor had it received any allegations related to, this individual," reads the statement from the district.

Waskowski is scheduled for a preliminary court hearing on Dec. 23.

Eastpointe is a suburb of Detroit, with about 34,000 residents.

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