Students and faculty members at Oregon State University have been warned to stay alert after secretly filmed videos of women walking on campus were discovered on a porn website.

More than 50 videos showing women from behind have been uploaded to the site, the university wrote in a Facebook post Thursday.

All appeared to have been recorded on the university's main campus in Corvallis in recent weeks.

The statement explained that OSU's Department of Public Safety had received tips from two people about the videos, and emphasized that the women's faces were not visible. Those featured in them were not identified by name on the site.

Steve Clark, vice president of university relations and marketing, told NBC News that the school made the site aware and were informed that the videos were taken down Friday morning.

"It’s not our policy or practice to demand content be removed from social media and websites, unless we think it’s illegal," Clark said. "In this case, I would not have thought to request removal. While this is creepy, it’s not illegal."

The school's office of community conduct is investigating the matter but has yet to identify the culprit, according to Clark.

"It’s possible the student would be reviewed for their actions and may be removed if we find they violated our community standards," Clark said.

The university advised people to watch out for "an individual appearing to take unsolicited videos of people walking on campus or a person following others walking on a silver blue mountain bike with a phone in hand."