A former school administrator was convicted of statutory sexual assault involving a 14-year-old girl while he worked at a Mastery charter school in West Philadelphia, Delaware County District Attorney Katayoun M. Copeland said Wednesday.

Omar Harrison, 43, of Elkins Park, was the dean of students at Mastery Charter School at Harrity, a K-8 charter at 5601 Christian St., in June 2017 when he took the girl to the Econo Lodge in Tinicum Township and committed the assault. The victim had been an eighth-grade student during the previous school year.

Harrison was arrested shortly after the girl's mother went to the school and confronted him about what had happened.

A Delaware County jury on Monday also found Harrison guilty of two counts of involuntary deviate sexual intercourse with a child less than 16 years of age, institutional sexual assault, and related offenses. He is scheduled to be sentenced Feb. 5.