An Edinburgh mum has warned other parents after reports of a 'suicide game' swept social media.

Parents across the UK have shared posts about what is known as the Momo Challenge, an online game that is played via social media platforms including WhatsApp, Facebook and YouTube. 

The challenge encourages children to hurt themselves after they have been invited to take part by an anonymous controller.

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The game is illustrated by a terrifying bug-eyed female face and shares violent images and threatens its users. 

It is thought that instances of the game have been reported in Colombia, Australia, Mexico and England and has been linked to at least two deaths. 

Lyn Dixon's eight-year-old son was left terrified last year when he came into contact with the game. Despite applying strict parental controls onto his use of the internet, images of the Momo face popped up on YouTube when he was watching harmless prank videos.

Lyn said: "It started with him not wanting to go upstairs on his own because it was dark up there. He was terrified and wouldn't sleep in his own bed and then we got to the bottom of it and we explained it wasn't real."

Lynn and her husband informed their son's school who gave an internet safety to talk to its pupils. It was not the first time teachers had heard of the sinister game.

But her son was scared for months after being exposed to the challenge and Lynn was worried when he told her he had seen it again recently.

Lyn said: "He showed me an image of the face on my phone and said that she had told him to go into the kitchen drawer and take out a knife and put it into his neck.

"We've told him it's a load of rubbish and there are bad people out there who do bad things but it's frightening, really frightening."

The face associated with Momo was created by a Japanese special effects company and has no affiliation with the game.

After another mum shared a post on a Scottish Facebook group last week scores of parents commented that their children had been exposed to the challenge. The original poster tells how her niece was told to 'sacrifice' herself for her brother.

Lyn said: "It's a big fear, that we can't always control what he's exposed to on the internet. You read these stories about children committing suicide and we all know how difficult life is now with the pressures on children. Social media is a massive part of that. It's horrific and we've got no control over it."

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Lyn's son has a mobile phone which is checked by his parents regularly but even though they have applied strict controls, Lyn still worries. She said: "There are controls on the phone but it doesn't go to the degree I would like it to because it's what you can't see that's the worry."

An NSPCC Scotland spokesman said: "The constantly evolving digital world means a steady influx of new apps and games and can be hard for parents to keep track of. 

"That’s why it’s important for parents to talk regularly with children about these apps and games and the potential risks they can be exposed to. 

"The NSPCC publishes advice and guidance for parents on discussing online safety with their children, as well as Net Aware – the UK’s only parental guide to social media and gaming apps."