WATCH LIVE: Officials hold news conference on De La Salle student arrested for alleged sexual assault
Police say the victim is a girl from Carondelet High School, an all-girls Catholic school next door to De La Salle.
Investigators say the attack happened on November 18 on the De La Salle campus after a football game.
The De La Salle student's identity has not been released and that the district attorney will determine whether to file criminal charges.