A British man at the center of one of the world's biggest catfish investigations has been jailed for a minimum of 20 years after admitting 185 charges involving 70 children.
Alexander McCartney, 26, posed as a teenage girl to befriend young women on Snapchat before blackmailing them.
Cimarron Thomas, 12, from West Virginia in the US, took her own life in May 2018 rather than comply with McCartney's demands to involve her younger sister in sex acts.
Cimarron's heartbroken father, Ben, died by suicide eighteen months later, not knowing what had caused his daughter to commit suicide.
In handing down a life sentence to McCartney at Belfast Crown Court on Friday, Judge O'Hara said he must serve 20 years in prison before he can be considered for release.
He told the court that the five years McCartney had already spent in custody would serve as part of his sentence.
"As a result, he will be eligible for release by the parole commissioners, but not until 2039," he said.
"I am not jealous of the commissioners who have to make their decision at that moment."
He told Belfast Crown Court: "To my knowledge there has been no case like this where a defendant has used social media on an industrial scale to cause such terrible and catastrophic harm to young girls, up to and including the death of a woman. 12 year old girl.
"The suspect was ruthless. He ignored several opportunities to quit. He ignored several pleas for mercy. He lied and lied and lied again."
The judge added: "In my judgment it is truly difficult to think of a sexual deviant who poses a greater risk than this defendant."
McCartney previously pleaded guilty to manslaughter in connection with Cimarron's death.
He also admitted 59 counts of blackmail, dozens of charges relating to taking and distributing indecent photographs, and dozens of charges of inciting children to engage in sexual activity.
In a statement after McCartney's sentencing, Cimarron Thomas's grandparents said: "We are all devastated by the death of our granddaughter.
"We know that nothing we do or say will bring her back.
"But if we can help another family not have to go through what we went through, something good could come from her death.
"Parents, please keep the doors open for communication about the evil of some people online."
McCartney had first contacted Cimarron four days before her death and blackmailed her into sending images.
She thought the ordeal was over, but he contacted her again on May 10. The PSNI restored online conversation between the two.
Cimarron repeatedly asked McCartney to leave her alone as he forced her to send more photos. At one point she said, "I don't like this."
When she told McCartney she would call the police, he replied "IDC" (I don't care).
Victims identified around the world
Belfast Crown Court heard that a PSNI officer who viewed the material said Cimarron was "completely distraught and sobbing at the time".
McCartney demanded that she send photos of her nine-year-old sister. She replied: "Please, not her."
When Cimarron continued to refuse McCartney's demands, he began counting down thirty seconds before threatening to post photos of her online.
He told her: "I'm posting, bye. Ben Thomas first (Cimarron's father). He should see the photo first.'
Cimarron replied, "No, I will obey."
The conversation then stopped. Three minutes later, Cimarron's younger sister found her body lying on the floor of her parents' bedroom.
She grabbed her sister's phone and pressed the panic button, triggering a 911 call. Cimarron died later that night in hospital.
Victims have been identified around the world, including in Australia, New Zealand and the US.
McCartney, originally from Lissummon Road outside Newry, Northern Ireland, used his technical knowledge as a computer science student to carry out his crimes.
His offense was carried out from the bedroom of his parents' home.
One researcher described the extent of McCartney's offending as a "pedophile enterprise".
Police believe he may have targeted 3,500 children from around the world.
McCartney first became known to police in Northern Ireland in 2016 when he was arrested in connection with indecent images of children found on his electronic devices. At this stage no victims had been identified and he was released on bail. In 2018, he was arrested again for similar crimes.
Despite police attention and bail conditions, McCartney continued to offend. He replaced confiscated phones and laptops.
In March 2019, Police Scotland contacted the Police Service of Northern Ireland (PSNI) in relation to a report of a 13-year-old girl being groomed by an adult suspect believed to be living in Northern Ireland.
When police raided his home, he was in the middle of a trespass and Snapchat was open on one of his phones. Devices seized from his bedroom were found to contain hundreds of thousands of indecent photos and videos of underage girls.
'You're going to do what I say'
He targeted young girls who were vulnerable or had doubts about their sexual identity and body image. He would use this vulnerability to convince them to send a photo.
Once he had the image, McCartney went to the notes section of his phone, where he had a pre-prepared statement that he would cut and paste into the conversation.
The message usually reads, "Okay, I used a fake camera snap app. I have your face pic and nudes. You're going to do what I say for tonight, and then I'll leave afterwards. But if you don't do them, I'll upload everything online for everyone to see. understand?"
Although McCartney promised to leave the victims alone after one night, he often returned later to continue the abuse.
He blackmailed them into sending more images or engaging in sexual activity online, threatening to share the images with other pedophiles. He forced some children to abuse younger siblings or forced them to involve pets and objects.
On one occasion, it took only nine minutes for McCartney to meet a twelve-year-old girl for the first time until he groomed, blackmailed and abused her.
He told a victim who objected to his demands that he have people come to her house and rape her. Another who threatened to go to the police was told: "I'm safe, I've been doing this for over a year."