Volunteer moderators say part of YouTube's system for reporting sexualised comments left on children's videos has not been functioning correctly for more than a year.

Part of YouTube's system for reporting sexualised comments left on children's videos has not been functioning correctly for more than a year, volunteer moderators have told Trending.

Sources inside YouTube’s “Trusted Flagger” programme say there could be up to 100,000 predatory accounts leaving indecent comments on videos.

A BBC Trending investigation has discovered a flaw in a tool that enables the public to report abuse.

But YouTube says it reviews the "vast majority" of reports within 24 hours, and that it has taken steps to shut down predatory accounts.

Presenters: Elizabeth Cassin and Mike Wendling

Producer: Anisa Subedar

Image: Woman holding a tablet device with the YouTube logo showing on the screen.

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