Killer catfish abuser is jailed for 20 years: Alexander McCartney terrorised hundreds of underage victims including US girl, 12, who shot herself before her tormented father took his own life

Britain’s most prolific and deviant catfish abuser, who pushed a terrified 12-year-old girl to take her own life and left hundreds of others humiliated and degraded, was today sentenced to life with a minimum of 20 years.

Alexander McCartney, a 26-year-old computer science student, made Cimarron Thomas use her father’s gun to shoot himself in the head rather than submit to his perverted demands.

Her father Ben, a US Army veteran, later took his own life after being consumed by guilt for leaving his gun where his ‘angelic’ daughter had access to it.

McCartney, from Newry, South Armagh, had pleaded guilty to the manslaughter of Cimarron at her home in Bruceton Mills, West Virginia, at a hearing earlier this year.

He also admitted 184 other offenses of blackmail and inciting a child to engage in sexual activity.

A mugshot of Alexander McCartney who admitted manslaughter in connection with Cimarron’s death

Gruesome messages between Alexander McCartney and one of his underage victims expose his perverse tactics as he jokes and flirts before suddenly turning nasty.

Cimarron Thomas (left) with her father, a US Army veteran, Ben Thomas, who later took his own life after being consumed by guilt for leaving his gun where his daughter had access to it

The former University of Ulster student had posed as a teenage girl as she contacted hundreds of other young girls, many of whom were gay or unsure of their sexuality.

Using Snapchat and other social media, he persuaded them to send topless photos – before revealing they had been catfished.

Catfishing involves using a false identity online to befriend and exploit victims.

He had first contacted Cimarron Thomas in May 2018. After receiving intimate photos, he attempted to blackmail her into carrying out his deviant demands.

Despite tearfully begging 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 counting down and told her “goodbye and good luck.”

Alexander McCartney (pictured), 26, operated from the bedroom of his family home in rural Northern Ireland, convincing young girls to send nude photos of themselves

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

Cimarron Thomas (pictured) was blackmailed online by McCartney and used her father’s gun to commit suicide

The boy was found dying by her nine-year-old sister.

Police investigating McCartney today released the 911 call from a neighbor who rushed to help the young girl.

Much of the call is muffled, but the 911 operator can be heard telling the neighbor to apply pressure to the head wound.

Cimarron’s 40-year-old father Ben took his own life eighteen months after her death.

At the time, the rural town family had no idea why Cimarron had committed suicide.

It wasn’t until 2021, when police found a transcript of the conversation between Cimarron and McCartney, that they were able to tell them the reason for her death.

He had kept the online chat on his computer as a ‘trophy’.

Cimarron (pictured with her father Ben) was told that if she did not comply with McCartney’s requests, her photos would be sent to her father

Cimarron’s mother Stephanie (pictured left) is still struggling to cope with the loss of her husband and daughter six years after the double tragedy. She is pictured here with Cimarron

The Thomas family initially had no idea why their daughter (pictured) had taken her life and were unaware of the depravity she had been exposed to

Relatives told MailOnline that the evil McCartney ‘might as well have pulled the trigger’ and were outraged that he was not charged with murder.

They had hoped he would be extradited to the US, but State Department authorities say that will not happen.

Members of the Thomas family said the double tragedy had torn their family apart, with Cimarron’s mother Stephanie suffering from PTSD and unable to talk about her daughter’s death six years later.

Prosecutor David McDowell spent 90 minutes describing how McCartney had “degraded and humiliated” his victims and showed no mercy when they begged him to stop.

McCartney refused to listen to the heartbreaking details of his campaign of abuse as he sat in the dock with his head bowed and his hands over his ears.

Most of his victims were aged between 10 and 16 and lived in Britain, Europe, America, Australia and New Zealand.

McCartney used his technical knowledge as a computer science student to carry out his crimes, prosecutors said

Cimarron Thomas, 12, (pictured) used her father’s gun to commit suicide after being blackmailed by McCartney online

A tribute to Cimarron Thomas, 12, (pictured center of frame) who committed suicide

McCartney pretended to be a girl and befriended girls who were said to be struggling with sexuality.

He flattered them into getting a compromising photo and then used it to blackmail and threaten the teens into committing heinous acts.

Each victim was terrified that their intimate photos would be exposed to family and friends.

McCartney told a girl that he would have people come to her house and rape her if she didn’t comply.

When another said her mother was dying of cancer, he said, “I don’t care,” and continued his brutal abuse.

Prosecutors said he committed the abuse for his own sexual gratification.

It only ended after a girl in Scotland complained she was a victim of catfish and the largest catfish survey in Britain was launched.

In March 2019, police in Scotland contacted their counterparts in Northern Ireland about a 13-year-old girl who had been groomed by an adult using the alias of someone her age.

McCartney was tracked down and arrested. Police seized 64 devices and found tens of thousands of images of underage girls performing sex acts while being blackmailed.

His lawyers said McCartney had shown genuine remorse and had spent five years in custody since his arrest in 2019.