WAYNE, Pa. » A man sneaking around on his hands and knees videotaped dozens of naked girls and women in dressing rooms at one of the country’s largest malls and then posted the clips on pornography websites, police said Monday.

Sean Moses, who admitted what he did, is seen on a cellphone video he recorded at the King of Prussia Mall outside Philadelphia reaching under doors to videotape women changing in dressing rooms at stores including Forever 21 and Express, police said.

Detectives called it one of the largest invasion-of-privacy cases they’ve seen in the area. They said Moses, a 37-year-old self-employed information technology worker, did it for "self-gratification" and kept "volumes of files on his computer known as jail bait" with videos of girls.

"You have young girls on a Saturday afternoon with their girlfriends, they go to try on some clothes and you have a pervert like this violating your personal space and your privacy," Radnor Township police Superintendent William Colarulo said.

Police arrested Moses on Monday at the Penn Valley home where he lives with his girlfriend and his 6-year-old daughter and charged him with dozens of counts of invasion of privacy and a count of child pornography. He was jailed in lieu of $500,000 bail. He couldn’t be reached for comment in jail and didn’t have a lawyer.

Colarulo said detectives found the videos posted on porn sites and tracked them back to Moses. From a previous unrelated incident, Detective Thomas Schreiber learned that people engaged in these crimes tend to post the videos online.

"He did an exhaustive search on the Internet and Detective Schreiber actually located the videos that Mr. Moses took of our unsuspecting victims," Colarulo said.

At least 69 videos were filmed at the Forever 21 store and posted online, according to an affidavit of probable cause.

Moses would lie on the floor of fitting rooms that had stalls that stopped about 2 feet from the floor, giving him "easy access to record from a ground up direction," the affidavit said. In the videos, one woman sees the camera and flashes an obscene gesture at it, and another woman takes a photo of it, but neither came forward to police. A complaint was filed by a mother and a daughter in December, but they never reported the incident to the police.

A spokesman for the mall did not immediately respond to a request for comment.

Police have worked to scrub the videos from the Internet, but Colarulo said they keep appearing because of the loyal following Moses had online.

"Mr. Moses had such a following on the Internet that even though these videos were removed, his fans are reposting these videos as a tribute to Mr. Moses because he actually had a fan club," Colarulo said.

Police said they started investigating allegations of video voyeurism against Moses in September, when two Villanova University students in Bryn Mawr reported seeing a camera light in their window. Police said they found a video Moses uploaded of the women labeled "Amazing Brunette and roommate who noticed peep."