Google-owned YouTube said Thursday it was taking action to close a loophole that enabled users to share comments and links on child pornography over the video-sharing service.
The response came after a YouTube creator this week revealed what he called a "wormhole" that allowed comments and connections on child porn alongside innocuous videos.
"Any content—including comments—that endangers minors is abhorrent and we have clear policies prohibiting this on YouTube," a spokesman said in an email to AFP.
"We took immediate action by deleting accounts and channels, reporting illegal activity to authorities and disabling comments on tens of millions of videos that include minors. There's more to be done, and we continue to work to improve and catch abuse more quickly."
The move came after Matt Watson, a YouTube creator with some 26,000 subscribers, revealed the workings of what he termed a "wormhole" into a pedophile ring that allowed users to trade social media contacts and links to child porn in YouTube comments.
Watson, who uses the name MattsWhatItIs, added that YouTube's recommendation algorithm "due to some kind of glitch is actually facilitating this."
Because ads automatically appear with many YouTube videos, Watson said the actions of the company amounted to "monetizing" the exploitation.
The post by Watson sparked a series of news reports, and according to some media, boycotts of YouTube ads from major firms including Nestle and Disney.
AT&T, which owns the WarnerMedia entertainment unit, confirmed it was pulling its ads from the service.
"Until Google can protect our brand from offensive content of any kind, we are removing all advertising from YouTube," AT&T said in a statement to AFP.
Epic Games, known for its popular online game Fortnite, said it was suspending ads on YouTube following the news.
"We have paused all pre-roll advertising" on YouTube, a company spokesman said.
"Through our advertising agency, we have reached out to Google/YouTube to determine actions they'll take to eliminate this type of content from their service."
The glitch appeared to allow some users to circumvent bans on child porn by Google and other internet platforms.
The incident raised fears of a fresh "brand safety" crisis for YouTube, which lost advertisers last year following revelations that messages appeared on channels promoting conspiracy theories, white nationalism and other objectionable content.
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