The American father and daughter, 12, driven to suicide by a 'catfish' in Northern Ireland

Cimarron Thomas, 12, took her own life with her father's handgun, rather than comply with the demands of the UK's most prolific catfish.

Warning: This article contains details readers may find distressing.

Her heartbreaking death had equally tragic repercussions, when her father Ben Thomas, a former US Army veteran, died by suicide 18 months after his daughter.

The child, from West Virginia in the United States, can now be named in the UK, after an anonymity order was lifted by a judge in Belfast.

Alexander McCartney, 26, a former computer student from County Armagh in Northern Ireland, pleaded guilty to her manslaughter and is likely to be sentenced next week after targeting at least 70 children online.

Posing as a girl, he befriended youngsters on social media, then used images they had sent him to demand more, a practice known as catfishing.

His victims in "the UK's largest catfish case" were aged between 10 and 16, and located in the UK, continental Europe, America, Australia and New Zealand.

He had previously admitted a total of 185 charges, including blackmail, inciting a child to engage in sexual activity and producing and distributing indecent images of children.

The prosecution said he had been "particularly callous", deliberately targeting victims who were either gay or exploring their sexuality and had "degraded and humiliated them".

A barrister said the harm he caused is "unquantifiable".

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Much of the detail in the case is too graphic and disturbing to detail. In a pre-sentence hearing, the judge called it "excruciating".

McCartney told one girl he would send people to her home to rape her if she didn't comply. In some instances, he demanded his victims involve younger siblings.

Cimarron Thomas was found dead by her nine-year-old sister.

In an impact statement, her grandparents said: "Our lives will never be the same.

"We didn't get to see her graduate, walk down the aisle or have children. We have been robbed of those memories. Our lives have changed forever."

:: Anyone feeling emotionally distressed or suicidal can call Samaritans for help on 116 123 or email jo@samaritans.org in the UK. In the US, call the Samaritans branch in your area or 1 (800) 273-TALK.

(c) Sky News 2024: The American father and daughter, 12, driven to suicide by a 'catfish' in Northern Ireland