Northeast High staffer accused of sex with student

A Philadelphia School District employee accused of having sex with a 17-year-old Northeast High School student surrendered to police Tuesday on sexual-assault charges.

Mark Preston Williams, 56, was charged with institutional sexual assault of a student, endangering the welfare of a child, and related offenses.

Williams was a staffer in Northeast High's Dean of Students Office when police notified the district Feb. 11 of the allegations against him, district spokesman Fernando Gallard said. Williams was reassigned the next day to a nonschool site that students do not attend, Gallard said.

The district intends to suspend Williams without pay, Gallard said.

The crime of institutional sexual assault of a student, a felony in the third degree, was signed into law in December 2011. The crime makes it illegal for a teacher to have sex with a secondary school student with whom the teacher has direct contact regardless of the victim's age.

The District Attorney's Office did not give a date or time of the alleged sexual assault, saying the case was still under investigation.