YUCAIPA (CBSLA.com) —     Officials with Yucaipa High School said they became aware last Thursday of an inappropriate sexual relationship between one of their employees and a female minor.

The school reported the allegations to the San Bernardino County Sheriff’s Yucaipa Station and to San Bernardino County Children and Family Services.

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Detectives at the Yucaipa Station, in turn, contacted the Sheriff’s Specialized Investigations Division – Crimes Against Children Detail (CACD) for assistance. Detectives launched an investigation, gathered evidence, and conducted numerous interviews.

Investigators determined Trevor Jack Trathen, 26,  had participated in illegal sexual conduct with the victim in February and March of 2014.

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At the time, Trathen was a coach at the Yucaipa High School and met the victim while she was a student at the school. Trathen was a substitute teacher at the Yucaipa High School at the time of his arrest. Officials said he has been removed from the Yucaipa/Calimesa School District Substitute System.

Trathen was arrested on September 2, at about 12:02 a.m.  He was booked at the Sheriff’s Central Detention Center for oral copulation with a minor 14-years of age and penetration with a foreign object on a minor 14 years of age.

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He is being held in lieu of $200,000 bail. Detectives are releasing Trathen’s booking photo in the event there are additional victims or witnesses.