A man secretly filmed a woman with smart glasses, before demanding money to take down the video he uploaded online.

The woman told the BBC that when the man first approached her while she was walking into a London shopping center, she had no idea she was being filmed.

“In the moment I just thought ‘OK this guy is just trying to talk to me, to chat me up,'” she said (the broadcaster didn’t reveal her real name, but identified her as Alice.) “I was hoping that he would leave me alone eventually but he did actually follow me.”

Alice only realized what happened when a friend sent her the video, which had racked up about 40,000 views.

“My initial reaction was complete shock,” she said. “He had no phone, he did not have a camera directly in my face.”

The alleged encounter grimly underscores the privacy and safety concerns that critics have raised over smart glasses. Since they appear like ordinary shades, they can be easily misused to film people — women especially, in practice —without their knowledge or consent.

Often, there can be no real means of recourse. Earlier this year, another woman in the UK discovered she was in a viral video with over a million views that was filmed by a man’s smart glasses. Horrified by the droves of comments berating and sexualizing her, she reported the video to authorities, but the police said there was nothing they could do because filming people in public wasn’t illegal.

Alice’s experience was no less harrowing. She told the BBC that when she contacted the man’s account asking to remove the video of her, the man replied that his video “fully complies with the law” and that he wasn’t “required to take it down.”

“That said, I understand that sometimes people may still prefer for certain content to be removed,” he wrote in an email obtained by the BBC. “In such cases, I usually offer the option of removal as a paid service, since it means taking down content that I’ve invested time, effort, and resources into creating.”

Alice refused to pay the man.

“It made me feel exploited, powerless,” she said. She reported the incident to the police, but in a statement to the BBC the Metropolitan Police said its “officers were unable to progress the investigation due to limited information.”

After TikTok took down the man’s video, he re-posted it to another social media site, according to the BBC. TikTok has now banned his account for violating its rules on bullying and harassment. Meta has taken down a video of Alice he reposted, and his YouTube account is inactive.

“He’s got the file, which still makes me feel uneasy, still constantly having to check back and see if he is uploading the video again. I just feel powerless,” Alice told the BBC. “If you don’t consent to content being out there of yourself, it can actually be very dangerous. It’s just a complete breach of privacy and data.”

According to the reporting, Alice isn’t alone. Another woman also contacted the same man asking to remove his content that depicted her.

More on privacy: Meta Had the Worst Possible Response When Its Workers Were Watching Naked Footage of Its Ray-Ban AI Glasses Users