Warning: This story contains distressing details of extreme child sexual abuse
A man from Northern Ireland has been given a life sentence with a minimum of 20 years in jail for the extreme online sexual abuse of children and the manslaughter of a 12-year-old girl.
Alexander McCartney, 26, from County Armagh, admitted 185 charges - including more than 50 blackmail offences.
Now one of the world's most prolific online child abusers, he created fake personas to target as many as 3,500 victims, aged 10 to 16, from more than 30 countries.
He pleaded guilty to manslaughter after a 12-year-old girl from the United States, Cimarron Thomas, took her own life in 2018 while he was abusing her.
- As it happened: Alexander McCartney jailed for minimum of 20 years
On Friday, Mr Justice O'Hara told Belfast Crown Court that McCartney, who has been in custody for five years, would not be considered for release before 2039.
He said: "I do not sense remorse or shame."
He added it was hard to think of “a sexual deviant who poses more risk than this defendant”.
What is catfishing and what did McCartney do?
Warning: Distressing details of extreme child abuse and strong language are mentioned in the section below.
Alexander McCartney's litany of crimes between 2013 and 2019 has been described as "the UK's largest catfishing case".
Catfishing involves the use of a false identity online to befriend and exploit victims.
The 'catfish' is the person who has created the fake persona.
They target people through social media and messaging apps, usually for abuse and fraud.
From behind a computer screen at his home in Northern Ireland, McCartney brought fear and devastation to the lives of thousands of children across the world.
He approached the vast majority of his victims on Snapchat, although on a small number of occasions he used other social media sites including Instagram and Kik.
On his 64 devices, he pretended to be a young girl to lure his victims into sending intimate photos.
Sometimes he used pictures he had obtained from other young girls and pretended to be them when speaking to new victims.
Once he had the photos he would blackmail them for more extreme photographs.
If they did not send them he said he would expose them to their friends and family.
He forced the children to involve their younger siblings in the abuse, which also included family pets and objects.
A spokesperson for Snapchat said the sexual exploitation of any person is horrific and illegal and "our hearts go out to the victims in this case".
“If we discover this activity, or it is reported to us, we remove it, lock the violating account and report it to the authorities."
The company said it had extra protections for teenagers to make it difficult for them to be contacted by strangers.
“Through our in-app Family Centre parents can also see who their teens are talking to, and who their friends are," they added.
In many cases terrified children begged McCartney to stop and begged that their pictures would not be put on the internet.
Some said they would kill or harm themselves.
One victim sent a picture with a cut on her arm. McCartney told them that he "didn’t give a shit".
Another girl said: “I can't stop shaking, I think I’m going to die.”
McCartney replied: “I don’t care.”
The police have said on occasions he shared the images with other paedophiles.
He kept records of the children he had abused and screenshotted their Snapchat location pins so he knew where they were based.
He was so relentless in his abuse that he had a template of messages that he would copy and paste to the children.
The court heard the harm McCartney caused was "unquantifiable" and he "degraded and humiliated" victims for his own sexual gratification.
Many of his child victims have never been identified, but all their lives have been changed forever.
Cimarron Thomas
Although investigators believe as many as 3,500 children were targeted; this case focussed on 70 of them in order to provide a manageable caseload for the court.
During the investigation, prosecutors discovered one case that had led to tragic consequences.
In 2018, he messaged 12-year-old Cimarron Thomas in West Virginia, USA. After complimenting her and getting a picture, he began his campaign of abuse.
He demanded more pictures of her and threatened to put her pictures online and expose her if she did not do what he said.
Scared, she did not tell anyone what was happening to her.
McCartney kept pursuing her and coming back for more photos and told her she had to include her little sister.
She refused to do so and said she would kill herself. He put up a countdown clock.
Cimarron shot herself in the head with her family's legally held firearm, while she was still online with McCartney.
Her younger sister found her.
Tragically, 18 months later, Cimarron's father Ben took his own life. When he died he did not know the reason why Cimarron had taken hers.
In a statement read outside the court on Friday, Cimarron's grandparents, Peggy and Dale Thomas, called on parents to “please keep the doors of communication open concerning the evil of some people online”.
McCartney pleaded guilty to the manslaughter of Cimarron Thomas earlier this year.
'A disgusting child predator'
On Friday, the Police Service of Northern Ireland (PSNI) said it was initially contacted following a report from Police Scotland that a 13-year-old girl had been groomed by an adult suspect believed to be residing in Northern Ireland, using the alias of a 13-year-old girl.
PSNI Det Ch Supt Eamonn Corrigan welcomed the sentencing and said McCartney is “nothing but a disgusting child predator”.
He added McCartney’s devices had "tens of thousands of photos and videos of underage girls performing sexual acts whilst being blackmailed”.
The detective said working with Homeland Security, the Public Prosecution Service and National Crime Agency, victims were located in America, New Zealand and at least 28 other countries.
“As far as I am concerned there is only one place for McCartney and that is behind bars,” Det Ch Supt Corrigan said.
Police said McCartney had become the first person in the UK to be sentenced for manslaughter when the victim resided in a foreign jurisdiction.
McCartney “may as well have pulled the trigger himself”, Mr Corrigan continued.
Catherine Kierans, acting head of the Public Prosecution Service Serious Crime Unit, said McCartney has caused "immeasurable damage".
US Homeland Security added McCartney deserved every minute of his sentence.
“We are thankful that our law enforcement partners in Northern Ireland saw fit to apprehend and charge McCartney for his role in the girl’s death," Special Agent Derek W Gordon said.
In a statement, Justice Minister Naomi Long said she hopes the sentencing will "serve as a deterrent and a reminder to other predators that online abuse is not beyond the reach of the law".
If you have been affected by any of the issues raised in this article, support is available via the BBC Action Line.
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