Momo 'challenge': The true story behind the horrifying trend police say is terrorising children

The image known as "Momo", now apparently being used to torment and horrify children on messaging apps such as WhatsApp, has once again been the subject of a series of warnings.

Police have this week expressed concern about the image, which they say is being used by cyber criminals and other malicious actors to add people on messaging services apparently in an attempt to steal from them.

But it is a long-running trend that has spread across the internet in a variety of different forms, with a true story that is almost as strange as the often troubling false stories that are told about it.

Relatively little is known about where the Momo image, name, or story came from. But it is far from supernatural and mostly explicable.

The image seems to have started life as a sculpture that was made for an art exhibit in Japan, three years ago. The model was made by a special effects company called Link Factory.

In its original incarnation, it was actually more strange than the picture that is usually passed around now.

As well as the infamous image of the young woman with thin, long hair and an unusual distorted face, the original sculpture had the body of a bird, though that now tends to be cut off from images when they are shared online.

The photo seems to been first shared on the internet around August 2016. But it was not until it was posted on the r/creepy Reddit forum that it picked up momentum, prompting internet users to begin concocting stories around it.

It is not clear where the name came from, and it does not appear to have emerged at the same time as the picture. But the two have become inextricably attached, and the photo is now universally referred to as Momo.

Once all of those different constituent parts were together, people gradually added to the myth – through stories that suggested the picture and the being it depicted were somehow supernatural, in YouTube videos and other online contect that claimed the "Momo" character was calling up people in the night and terrorising them.

At the same time, its use as a prank - that people could use with varying degrees of malice to attack others - began.

It has often been hard to separate the reality from the truth and some of the stories linked to the image in stories told on the internet have now been accepted as fact.

As with many things now referred to as "challenges" by newspapers, the new Momo trend is not really a challenge in the traditional sense, or even in the more recent interpretation of the word that has flourished through popular phenomena such as the Ice Bucket Challenge.

Instead, a more accurate descriptor might be a meme, though of course this is not one filled with the kind of fun or joy that word might normally be associated with. There is no real challenge involved, more just a diffuse set of different things people are using the image for.

The most chilling one of those – and that which police recently warned people about – is people using that image as their own profile picture and the name Momo adding people on WhatsApp. They will then send messages that range from the mildly strange to the genuinely unsettling, and even dangerous.

Of course, anyone is able to access the image online, add it to their WhatsApp, and add whoever they like. It means there are as many different ways of using the image as there are people doing it.

Some people may be using the picture for relatively non-malevolent – though of course still unpleasant – purposes, such as freaking out their friends in behaviour they might understand as a prank.

Others might be using it for altogether more malicious purposes, such as cyber bullying or sending genuinely concerning messages, with reported examples of a child being told to hold a knife to their throat or having their family threatened.

In all instances, advice from cyber security experts is the same: be careful about anyone that might add you or children you are responsible for on WhatsApp, whether or not they are using the image.

"Adding someone on WhatsApp may seem harmless or even fun at first but it can be very damaging in the future once they are a 'contact', especially if this new connection then asks you to act out something you usually would not feel comfortable in participating in," said Jake Moore, cyber security specialist at ESET.