An investigation has found Facebook groups where thousands of users share “upskirt” pictures and videos of unsuspecting women and girls, the BBC reports. The news service says it uncovered swathes of obscene material obtained by perverts secretly recording women and girls in public, and also found people asking for tips on how to get away with shooting upskirt images. Reporters even said they had informed the NYPD of one user who followed a schoolgirl up steps in New York in order to film up her skirt and share the footage on Facebook. Facebook deleted the user’s account, but the BBC said some of the images it reported to the social media platform using Facebook’s own safety tools weren’t initially taken down. Meta, Facebook’s owner, has said it removed a “large number” of such groups following the investigation.