Officers are hunting members of loose online networks of sadists who mainly targets girls on gaming platforms and social media.

By Chris Clements Detectives in Scotland have joined international law enforcement in targeting online gangs which groom and coerce children into acts of self-harm.

The groups, mostly comprised of teenage and young adult males, have risen in prominence in recent years after cases involving sextortion and hacking, as well as self-harm encouragement.

So far, there has been one arrest in Scotland, while there have been a handful of convictions in England.

The Molly Rose Foundation - a suicide prevention charity helping young people and families victimised by the network - said the groups "represent the gravest risk to children online".

In a locked room at the force's Scottish Crime Campus, he is showing the BBC images on a computer sent to the team by the National Crime Agency (NCA).

Flagged by National Centre for Missing and Exploited Children (NCMEC) in the United States, the material was eventually passed to Police Scotland and on to Paul's desk.

He now has the job of sifting through horrific images of abuse and injury in order to identify the victim, as well as the Scottish perpetrator.

"Unfortunately, we are getting a lot of self-harm imagery," he tells BBC News.

"There's nearly a thousand images in this particular case, and we need to go through every single one of those." Abuse for 'kudos' This case is linked to a Com group - a violent collective that uses mainstream social media platforms to manipulate and blackmail girls into harming and abusing themselves.

Often, the police say, this is done by the group for "kudos", or clout, from their peers.

On the screen, one image show a young girl's arm covered in blood. Another shows blood used to daub a symbol on to a bathroom wall.

Paul alleges the girl in the case was directed to harm herself by someone she met online - understood to be a young male in Scotland.

"Usually, it's a young girl in these particular cases," Craig said. "We're finding a lot of vulnerable young girls that are between 11 and 17.

"Unfortunately, we discover down the line that there are other vulnerabilities that [perpetrators] are exploiting." Among the pictures are occult or Satanic sigils, a way for the abusers to appear "as extreme as possible", says Craig.

He continues: "It's very common, but I don't think they believe these Satanic things.

"With these particular groups anyway, it's about how extreme, how much exploitation can you inflict on an individual.

"It's about how much control you can get, up to the point that they're getting them to self-harm." The Com - short for "the community" - are loosely-affiliated online groups involved in acts of abuse, financial crimes and extremism.

Groups involved in recent court cases include "The 764" and "CVLT". However, membership and group dynamics shift over time.

In May, the NCA said it was investigating around 200 cases involving these networks, while there have been a number of convictions.

In August, 20-year-old Justin Swaddle was jailed for two years for blackmailing and coercing more than 100 victims into acts of self-harm, including carving his online username on their bodies.

Det Ch Insp Craig Faulds - who leads efforts targeting groups' links to Scotland - described the crimes as "an evolution of online child abuse and sexual exploitation".

He told the BBC that often abusers will target their victims on "innocuous gaming platforms".

He continued: "It can move to social media platforms, messaging services and online forums.

"We are seeing cases where perpetrators online are targeting young vulnerable people, usually girls, and they are manipulating them, they are coercing them into sharing indecent images of themselves. "Some of the more serious cases are seen by coercing individuals to cause acts of serious self-harm.

"We have identified victims and perpetrators in Scotland. And we are at the stage of mapping this threat to understand significance and the prevalence of it."

Who are the abusers? Hazel Stewart, who works for the NCA's Threat Leadership team, described the prevalence of Com groups are "low-volume, high-harm", adding: "The scale doesn't matter, it is the harm that is being caused." She told the BBC that the abusers themselves are often young males who have been socially isolated or bullied.

"They find their own identity online, they can be whoever they want to be," she said.

"And therefore they are encouraging those that are vulnerable, usually young females... seeking them out, say, on suicidal ideation sites or eating disorder sites, and encourage them into more private spaces." Stewart explained that abusers form relationships with victims and "be very supportive at first" before encouraging them to carry out harmful acts.

"It might be a small cut at first. Or it might be harm to a pet, or a sibling," she said.

"That harm will escalate and the grooming and manipulation continues, and the victim is in a situation where they can't escape." Stewart described the threat as a "global problem" and said the UK was working with law enforcement in the USA, Australia, Canada and New Zealand, as well as Interpol and Europol.

The Molly Rose Foundation has recently warned about Com networks. Its chief executive Andy Burrows said it was "becoming the frontline of child protection online".

He said that online safety regulator Ofcom had been warned about the threat of online gangs and had been slow to respond - a "failure" that he said highlighted weaknesses in the Online Safety Act.

He continued: "These networks represent the gravest risk to children online, with every UK police force investigating Com cases, the threat is real and widespread.

"It's also clear that these risks exist beyond just social media, on gaming platforms and encrypted messaging apps, which is why Andy Burnham must move beyond a blanket social media ban and incentivise all online platforms to become safe for young people as a price of doing business in the UK."

An Ofcom spokesperson said: "The threats posed by Com groups are a particular concern for Ofcom, and we're working closely with law enforcement and child protection agencies to tackle them. "Where services fail to comply with their duties, we've shown that we won't hesitate to act."

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