TREDYFFRIN TOWNSHIP, Pa. (CBS) — A Pennsylvania high school is facing a lawsuit after a student was allegedly sexually abused by a school aide.

A federal lawsuit was filed Thursday against the Tredyffrin-Easttown School District and the Conestoga High School principal in connection with allegations of sexual abuse of a student by 67-year-old Arthur Phillips.

Attorney Matt Casey, who represents the victim and her parents, says the suit alleges the school district created an environment which allowed Phillips to sexually abuse the 15-year-old girl.

“She was not only not protected, but she was horrifically abused, I mean in the most severe ways, by a gentleman at that school right under the noses of the people who were charged with preventing things like that from happening,” said Casey.

High School Employee Accused Of Sexually Assaulting Student

Casey says a number of teachers were aware of the relationship but failed to intervene.

“This was happening in the midst of another Conestoga employee being sentenced for sexual abuse involving another student at the same school,” said Casey.

The school district says the district and the principal had no knowledge of the ongoing behavior until Phillips’ arrest in April.

Casey says the sexual abuse happened while another high school staff member, 26-year-old teacher’s aide Christine Marie Towers, was being sentenced in a separate sex assault case.

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