Police said 21-year-old Ji Hun Choi admitted to following the woman to Roberts Hall Dormitory, taking video of her and touching her "bottom."

Security footage shows him following the suspect up the stairs, going off camera and then stumbling down the stairs to run away. In Choi's written statement to police, he said when he groped the woman she screamed and turned around, so he ran away.

Choi voluntarily also admitted to taking video of other women, without their consent. He is charged with improper photography, a state felony.