ARAPAHOE COUNTY, Colo. (CBS4) – A teacher is behind bars for allegedly sexually assaulting a student five years ago.

Investigators got a tip through the Safe2Tell notification system that a young woman was assaulted as a student five years ago.

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41-year-old Ian Ahern was arrested Friday after turning himself in. Ahern has been a teacher with Littleton Public Schools since 2010 as the drama teacher at Arapahoe High School.

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Ahern faces two counts of Sexual Assault on a Child by a person in a Position of Trust.

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No booking photo has been made available as the investigation continues.