Detectives missed TWO possibilities to cease Britain’s ‘most prolific catfisher’ Alexander McCartney who preyed on 3,500 ladies throughout 30 completely different nations

Detectives missed key chances to stop Britain’s worst catfisher while he preyed on 3,500 girls.

Alexander McCartney, 26, was jailed for life yesterday with a minimum of 20 years behind bars.

He claimed victims in 30 countries during a campaign that spanned at least five years.

By ‘catfishing’ – using a fake identity to deceive people online – as a young girl on the social-media app Snapchat, McCartney groomed, blackmail and abuse youngsters around the world.

One of his US victims, Cimarron Thomas, 12, shot herself in the head with her father’s handgun rather than submit to his sadistic demands.

Her father Ben, a US Army veteran, took his own life after being consumed with guilt for leaving his gun where she could access it at their home in West Virginia.

Alexander McCartney, 26, was jailed for life yesterday with a minimum of 20 years behind bars

McCartney, from County Armagh, Northern Ireland, pleaded guilty to Cimarron’s manslaughter and 184 other offences, relating to 70 sample cases, of blackmail and inciting a child to engage in sexual activity.

Following his sentencing at Belfast Crown Court yesterday, the Mail can reveal there were two missed chances to stop him, at least one of which could have saved Cimarron.

He was twice investigated on suspicion of amassing indecent images, in 2016 and 2018, but neither probe resulted in criminal charges.

His conduct only came to an end after a 13-year-old girl in Scotland revealed that she was a victim, and the UK’s biggest catfishing investigation was launched in 2019.

The missed opportunities to save potentially hundreds of girls are being investigated by the Northern Ireland Police Ombudsman.

Jailing McCartney, Mr Justice O’Hara said he was responsible for the ‘deviant and sadistic’ targeting of vulnerable victims on an ‘industrial scale’, adding: ‘I find it hard to think of a sexual deviant who poses more risk than this defendant.’

He described the former University of Ulster computer science student as being ‘devoid of normal human empathy’ and revelling in his ability to degrade his young victims.

McCartney, from County Armagh, Northern Ireland, pleaded guilty to Cimarron’s manslaughter and 184 other offences, relating to 70 sample cases, of blackmail and inciting a child to engage in sexual activity

Most of McCartney’s victims, who lived in countries including Britain, Europe, America, Australia and New Zealand, were aged ten to 16 but some were as young as four.

Detective Chief Superintendent Eamonn Corrigan, from the Police Service of Northern Ireland, said: ‘McCartney is nothing but a disgusting child predator who was posing as young girls online to groom, manipulate and sexually abuse his victims, as young as four, to satisfy his own sexual perversions and that of other child sexual offenders.’

McCartney contacted Cimarron in May 2018. After receiving intimate photos, he tried to blackmail her into carrying out his deviant demands. Even though she pleased tearfully with him to stop, McCartney threatened to send the photos to her father and friends. When she refused his demands and said she would shoot herself, he cruelly began a countdown and told her: ‘Goodbye and good luck.’

She was found dying by her nine-year-old sister.

The family had no idea why Cimarron had committed suicide – the reason only came to light in 2021 when police in Northern Ireland found a transcript of the conversation between Cimarron and McCartney, which he had kept as a ‘trophy’ on his computer.

Cimarron Thomas (right) with her US army veteran father Ben Thomas, who later took his own life after being consumed with guilt for leaving his gun where his daughter could access it

Cimarron and Ben Thomas with mother Stephanie. The double tragedy ripped apart the family

Cimarron’s family said McCartney ‘might as well have pulled the trigger’ and were outraged that he was not charged with murder.

Prosecutor David McDowell described how McCartney ‘degraded and humiliated’ his victims and showed no mercy when they pleaded with him to stop. McCartney, who refused to listen and sat in the dock with his hands covering his ears, told one girl that he would get people to come to her house to rape her if she didn’t comply.

When another said her mother was dying of cancer he said, ‘I don’t care’, and continued with his relentless abuse. Raised in a quiet farming community less than ten miles from the Irish border, McCartney lived with his father, a timber yard manager, mother and three siblings in a five-bedroom bungalow near Newry. From a young age, he showed an aptitude for computers, and went on to study computer science at university.

When the net closed in, police raided his home while he was in his bedroom, ‘literally in the middle of offending, with Snapchat open’, sources told the Mail. More than 60 digital devices were seized and examined forensically.

What they contained – graphic images, plus records of chats with terrified girls which McCartney had saved, apparently as trophies – shocked even hardened detectives.

Investigators in the US praised Snapchat’s co-operation after the firm provided ‘everything they could’ for the investigation.

One man who knows McCartney’s family told the Mail they were ‘very well-liked’, adding: ‘This must be hell for them.

‘It’s beyond disgusting what he did.’