How an online abuser destroyed a girl's life in his NI home

WARNING: This article deals with very disturbing topics and contains graphic details. It is not suitable for all target groups. Reader discretion is advised.

Cimarron Thomas took her own life after being blackmailed by an online abuser.

In her last online conversation with Alexander McCartney, he threatened to share inappropriate images – images he tricked the 12-year-old into sending – if she didn't send pictures of her younger sister.

He said the pictures would be sent to her father, other family members and friends.

Just over three minutes after the online chat ended, just before 1 a.m. on May 11, 2018, Cimarron took his own life.

Eighteen months later, in January 2020, her heartbroken father Ben Thomas, a former US Army veteran, also took his own life.

Family members said he lost the will to live and was overcome with guilt because his daughter had access to his gun.

A father and daughter in a small town in West Virginia in the US were driven to suicide by what prosecutors described as “depravity” by the actions of a serial child molester who used a computer in the bedroom of his Co Armagh home.

Many more lives were destroyed.

McCartney, originally from Lissummon Road outside Newry, pleaded guilty to the manslaughter of Cimarron Thomas and 184 other child abuse-related charges, including inciting children to engage in sexual activity and 59 counts of blackmail.

The offenses occurred between 2014 and 2019, starting when he was 17 and ending when he was 21.

There were 70 victims, all girls, who were between 10 and 16 years old at the time of the attacks via social media platforms, mostly Snapchat.

His victims were located all over the world, in Northern Ireland, the Republic of Ireland, continental Europe, the USA, Australia and New Zealand.

The actual number is believed to be much higher because some victims could not be identified and others refused to come forward due to the nature of the crime.

A lawyer for the Northern Ireland Crown Prosecution Service told the pre-sentence hearing that in all likelihood “there are many, many more victims” and that “the damage he has caused is therefore not quantifiable”.

The full details of this case could not have been revealed had a judge not lifted restrictions imposed by new sexual offenses laws introduced in Northern Ireland in September 2023.

The law grants victims of sex crimes anonymity for 25 years, including after their death.

This restriction was challenged by a number of media organizations and a judge agreed that there was a strong public interest in overturning the order in this case.

The full details of many of McCartney's criminal actions are too graphic and disturbing to report.

The prosecution barrister described his litany of crimes as “pretty horrific” and told the court his victims had been “degraded and humiliated”.

McCartney, a former computer science student at Ulster University, engaged in a practice known as “catfishing” – the use of a false identity to befriend victims and then exploit them.

The sentencing hearing was told that McCartney found and befriended young girls who were said to be struggling with their sexuality and exploited their insecurities.

Cimarron's sister told police that the 12-year-old told her parents that she believed she was bisexual.

McCartney sent his victims a photo of a teenage girl pretending it was a picture of him, then deceived them by sending them compromising sexual images of themselves, usually topless.

The court was told he did this through a combination of flattery and persuasion, complimenting them on their looks and assuring them of their attractiveness.

When they sent the image, he then revealed his true identity and threatened them with exposure if they did not perform sexual acts on themselves and, in some cases, younger children. Some of those he requested were as young as three and five years old.

He told the children that if they did not follow his instructions, he would upload the image online or send it to their friends and contacts on their social media accounts.

McCartney sent his victims pictures with their locations on Snapmaps, showing that he knew where they lived and went to school.

The investigation into his activities is believed to have been one of the largest in the world, involving an international effort involving numerous police and law enforcement agencies.

He first came to the attention of police when a large number of electronic devices, including four laptops, eight computer tablets and nine mobile phones, were seized in January 2016 and contained 3,490 indecent images.

McCartney was arrested on February 4, 2016, before being released on police bail.

His home was searched in March 2018 and again the following year, March 2019, a week after the PSNI received a referral from Police Scotland alerting investigators that one of McCartney's victims had come forward there.

The most recent search occurred four months later, on July 30, 2019, when he was arrested again and charged with multiple offenses.

Despite police attention and multiple searches of his home, prosecutors said the severity of his behavior increased over time, in the form of the “depravity of the demands he made.”

Following his arrest in 2019, the PSNI contacted other police forces and law enforcement agencies to identify the children whose images they found in his possession.

The U.S. Homeland Security contacted the investigative team on January 20, 2021 and informed them that a Snapchat user, Cimarron Thomas of West Virginia, had taken her own life “while online with the defendant.” The chat conversation was recovered from McCartney's laptop.

When he first contacted Cimarron Thomas on May 7, 2018, just four days before her death, he pretended to be a girl named Sarah.

A transcript of parts of their conversations was provided to the court.

This revealed how he tricked his victim into sending a topless photo and video of himself.

Fifteen minutes later, McCartney revealed his true identity and told her: “I have your nudes and your face photo that you are going to take for tonight, what I say, otherwise I will upload everything online for everyone to see, for everyone too.” on your Instagram…Do it, do you understand?”

He then demanded a series of sexual images of the child and insisted that she also show her face.

A prosecution lawyer told the court: “It appears she was distressed and may have started crying.”

At one point, McCartney said to her, “Dry your eyes and look cute for me.”

Cimarron begged him not to send him a picture of her younger sister, but he persisted.

When the young girl wrote that she was going to take her own life, McCartney responded with “kk” – instant messaging slang for ok.

He told her she had 30 seconds to decide whether she would send the picture he requested, then counted down: “20, 15, 10, 0 times up.” He then added that he posted the pictures he had of her and that if she didn't send a photo with her sister within a minute, her father would be the first to see her.

“A minute is up. Well,” were the last words he posted.

Cimarra Thomas didn't answer.

A little more than three minutes later, her nine-year-old sister found Cimarron. The victim's family, including her father, had no idea why she took her own life until they were contacted by police and informed about online conversations with McCartney.

In a victim impact statement, the young girl's family said her life will never be the same.

“We didn’t get to see her graduate, walk down the aisle, or have children. We were robbed and our lives were changed forever,” they said.

The pre-sentence hearing also outlined the plight of the other victims targeted by McCartney.

Prosecutor David McDowell told the court some of the children's reactions were pathetic as, in desperation, they begged him to stop and sought assurances that their images would not be posted online or sent to their friends or family members.

“Many cry and tell him they are shaking,” he added.

“Some of his victims told him they were going to kill themselves while begging him to be left alone.

“Others threatened to harm themselves in desperation, some did so in front of the camera.”

When a victim repeatedly said she was killing herself and that her mother was dying of cancer and had a heart defect, McCartney responded: “I don't care about you or your mother.”

Another young girl was told that if she didn't comply with McCartney's demands, he would make people go to her house and rape her.

At the sentencing hearing, Judge O'Hara was told that some of the other victims had also prepared victim impact statements detailing the lasting impact of what McCartney did to them.

These included flashbacks, depression, anxiety, stress manifested in alopecia, shame, embarrassment, self-blame, loss of confidence in one's appearance and difficulty trusting others, as well as the impact on relationships.

In some cases, the parents of the victims wrote about the impact that what was done to their young children and their families had on themselves.

If you are affected by the issues raised in this article, support and help is available.