How police caught the catfish killer

It was a phone call from a 13-year-old girl in Scotland in 2019 that ultimately led to the capture of a social media predator described as one of the world’s most prolific child sex abusers.

Alexander McCartney, from Northern Ireland, posed as a teenager to befriend, then abuse and blackmail children around the world, often sharing images with other pedophiles.

Some of the children were as young as four years old. Some had never told anyone what had happened to them, until the police knocked on their door.

McCartney gradually admitted to 185 charges, including manslaughter After a 12-year-old girl he abused took her own life.

He has been sentenced to a minimum sentence of 20 years.

Following contact from Police Scotland, an urgent investigation by the Police Service of Northern Ireland (PSNI) was launched in March 2019.

Detectives identified Alexander McCartney’s home address, arrested him and interviewed him.

Sixty-four of McCartney’s devices were seized from his home in the rural Lissummon Road area outside Newry in four separate raids.

These devices contained hundreds of thousands of indecent photographs and videos of underage girls performing sexual acts while being blackmailed.

McCartney created and used many fake accounts on online platforms, primarily Snapchat, to trap and manipulate them.

PSNI Detective Eamonn Corrigan said McCartney had been “offending on an industrial scale”.

He groomed victims by making them believe they were talking to a girl of a similar age online, before encouraging them to send indecent images or engage in sexual activity via webcam or mobile phone.

McCartney used the same pattern each time, the detective said, adding: “He threatened to share these images online for the pleasure of other pedophiles and use them to further abuse and harass already terrorized and exploited children.”

In one incident, it took McCartney just nine minutes to groom, sexually abuse and blackmail a girl as young as 12.

As time passed, it became clear that McCartney’s depravity extended not only throughout the United Kingdom, but throughout the world. The abuse included involving other people, pets and family objects.

The PSNI worked with colleagues from the US Department of Homeland Security, the Attorney General’s Office and the National Crime Agency, and victims were located in the United States, New Zealand and at least 28 other countries.

Many of these children were only identified through evidence that detectives located on McCartney’s devices.

According to the police, he “built a pedophile enterprise” and “stole the childhood” of his victims.

In spring 2019, police called Catherine Kierans, acting head of the Public Prosecution Service’s serious crime unit.

They said “something big was developing… it was catfishing.”

Catfishing is where a person creates a false identity to gain people’s trust and exploit them.

Kierans said girls “of an average age of 10 to 12 were being threatened in the most depraved way”.

He said some of the children who had been exploited had previously spoken out about their abuse, others had remained silent.

“Some of the children had raised the alarm, which helped the police identify him in the first place.

“But some of the children, until the police came knocking, had never told anyone what they had been through.”

According to Kierans, McCartney offended “24 hours a day.”

As the investigation spread around the world, Kierans said prosecutors realized McCartney had been “very diligent in saving the footage.”

“I also saved the map on Snapchat of where the child was in some cases, and that allowed the police to locate the children.”

His 2021 arraignment was delayed when police discovered the suicide of a girl in West Virginia, US.

“From the beginning, the level of abuse was so appalling that we feared that when these children were identified, would they be okay?” Mrs. Kierans said.

“Unfortunately, our worst fears came true when we somehow discovered that one of the girls had taken her own life.

“Working closely with US authorities, we were able to prove that this girl took her own life during the abuse, while she was still online with McCartney.

“At the time, the girl’s death was so intrinsically linked to the abuse that we felt we had a strong case to say he killed her.”

That little girl was 12-year-old Cimarron Thomas, who, in 2018, shot herself while McCartney abused her.

McCartney was charged with involuntary manslaughter.

Kierans said it is believed to be the first time an abuser anywhere in the world has been held accountable for manslaughter in which the victim and perpetrator never met in person.

The magnitude of the case was such that prosecutors had to be judicious with the charges.

“We couldn’t fit 3,000 charges into the indictment,” Ms. Kierans said.

“In the end there were around 200 charges (relating to around 70 victims) which is probably one of the biggest allegations we have seen in Northern Ireland.”

McCartney grew up five miles from Newry and just off the main road to the city of Armagh.

It is as rural as possible. Farms, a church and some businesses.

When he first appeared at Newry Magistrates Court in July 2019, he was just 21 years old, with long, matted hair and the wide gaze of someone surprised to be sitting where he was.

He has spent more than five years on remand in Maghaberry prison, from which he only leaves to appear in court and be questioned by the police.

At those hearings, he said little more than confirming his name and date of birth and gradually quietly pleading guilty.

McCartney attended Newry High School and liked games.

A source told BBC News NI: “He was introverted and socially awkward. He didn’t interact much with people outside his friend group.

“Maybe I was on edge, but I had friends who obviously didn’t know about this.”

He then took a course at Southern Regional College in Newry, where he was described as “quiet and didn’t really engage with the rest of the class”.

When he was finally charged in 2019, he was a computing student at the University of Ulster.

For those who live in and around her home, the case has been heartbreaking.

“The whole place was stunned,” one resident said.

“At first it was whispers, then disbelief. “I’m sure people talk about it in their own homes, but it’s not discussed publicly because people don’t know what to say.”

Another said: “He seemed like a nice, affable and intelligent young man.

“There is nothing extraordinary about him.”

But what is extraordinary is the enormity of his offense; Many of his victims had pleaded for the abuse to end, but prosecutors said he “continued cruelly, at times forcing the victims to involve younger children, some as young as four years old.”

According to Catherine Kierans, McCartney’s depravity was such that it was “one of the most distressing and prolific cases of child sexual abuse we have ever seen in the PPS.”

Kierans said some of the victims have never been identified despite extensive efforts by police.

“McCartney’s crimes have harmed thousands of children and left them and their families dealing with traumatic consequences,” he said.

“His bravery is in stark contrast to his cowardice in attacking vulnerable girls.”

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