ST. PAUL, Minn. (AP) — A former Bemidji assistant school principal will serve 25 years in prison for using social media to direct dozens of girls and boys to send him sexually explicit photos.

Thirty-five-year-old Brandon Bjerknes was sentenced Tuesday in federal court in St. Paul. Bjerknes pleaded guilty in October to coercion of a minor and child pornography.

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Prosecutors say Bjerknes posed as a young teenage boy on social media, encouraging girls and boys as young as 12 to send him sexually explicit photos of themselves.

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Bjerknes became assistant principal at the middle school in 2014. He resigned last April and was arrested the next month.

The Star Tribune reports Bjerknes will be on supervised release for life and must register as a predatory offender.

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