AUSTIN -- University of Texas police arrested 21-year-old Ji Hun Choi for improper photography.
Investigators say he used his cellphone to record a woman walking seven blocks, nearly half a mile, to her dorm room. Once they arrived at Roberts Hall, police say Choi admits he grabbed the woman's backside. He told police he did it because the woman, "looked so good."
According to UT's website, Choi is a junior engineering major.
"It was crazy because he got inside the building, from the pictures, I don't know how he got in here," said Taylor Guerrero.
Guerrero lives in Roberts Hall. She says police notified her about the suspected attacker through campus email.
"Oh, I feel so bad for her. I don't even know what I would do if something like that happened," said Guerrero.
According to an arrest affidavit, Choi told police he recorded other women in the past without their consent. Police asked if he ever touched any of them. Officers say, "he would not answer."
"Pay attention to your surroundings and what's happening around you at all times," encouraged UT Police Asst. Chief Terry McMahan.
Police are searching Choi's phone for evidence of other crimes.