VAN NUYS (CNS) — A Los Angeles Unified School District assistant principal has pleaded not guilty to sex-related charges involving a 14-year-old student while he was assigned to a Van Nuys middle school in 2006.

William Webb, 51, was arrested and charged last month with one count each of committing a lewd act on a child, oral copulation of a person under 18 and sodomy of a person under 18.

Detectives with the LAPD’s Sexually Exploited Child Unit began investigating the allegations in February 2015 “after receiving a suspected child abuse report alleging that a prior student of Mr. Webb had been sexually abused by him while Webb was assigned to Vista Middle School,” according to a police statement.

Webb worked as a counselor at the middle school, according to the District Attorney’s Office.

Webb was assistant principal at Ramon C. Cortines School of Visual and Performing Arts in downtown Los Angeles, where he had worked since 2009, when the allegations first came to light in September 2014.

At that time, he was reassigned from the school to his home and the case was referred to the LAUSD’s Student Safety Investigation Team, which cooperated with the LAPD investigation, according to the school district.

Webb has been placed on unpaid involuntary leave, according to the LAUSD.