The eerie 'Momo challenge' has been blamed for terrifying children into hurting themselves or others, but experts say its influence has been greatly exaggerated.
An image of a spooky-looking woman - originally a Japanese statue called 'Mother Bird' - has circulated online since last year as part of a dangerous game for kids.
People who are sent a photo or video of Momo are supposedly told to carry out challenges escalating from cutting their own hair to even filming themselves taking their own life.
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In 2018, a 12-year-old girl committed suicide in Argentina, and some reports claimed she'd been playing the Momo game before her death. This was never confirmed.
While the meme first surfaced months ago, Momo has made fresh headlines worldwide in the past few days after rumours circulated that a character was appearing in YouTube videos and threatening to kill children and their families.
However several UK-based children's charities and internet safety experts have quashed the theory, and say it's yet another example of online hysteria based on little factual evidence.
The National Society for the Prevention of Cruelty to Children (NSPCC) says there's no evidence any children have actually been harmed by Momo. It says in the past few days, it's received more phone calls from journalists asking about the challenge than from any concerned parents.
The UK Safer Internet Centre called the phenomenon "fake news".
A spokesperson for charity Samaritans told The Guardian that disproportionate media coverage is "raising the risk of harm" for vulnerable young people.
"These stories being highly publicised and starting a panic means vulnerable people get to know about it and that creates a risk."
They said they're unaware of any verified evidence in any country that links Momo to real incidents of suicide.
"What's more important is parents and people who work with children concentrate on broad online safety guidelines."