Image source, Getty Images

Pretending to be a girl and operating mainly on Snapchat, McCartney found and befriended girls who were said to be struggling with sexuality all over the world.

He used flattery to get a compromising photograph and then used it to blackmail and threaten the children into committing appalling acts or he would publish the images online.

McCartney told one girl that he would get people to come to her house to rape her if she didn’t comply.

According to Catherine Kierans, acting head of the Public Prosecution Service’s serious crime unit, McCartney’s offending was relentless.

“You had little girls, an average age of 10-12 years old being threatened in the most depraved way," she told BBC News NI.

“It was around the clock, it was difficult to know when he was doing anything else.”

The victims spanned 30 countries; the abuse included involving other people, family pets and objects.

In one incident, it took McCartney just nine minutes to blackmail a child.

Image source, Dale Thomas

The identity of the little girl who took her own life after being abused by McCartney can now be revealed as 12-year-old Cimarron Thomas.

Cimarron lived in West Virginia, USA, with her mum, dad and siblings.

She played the violin, she loved elephants and chatting with her friends on Snapchat.

They were an ordinary American family but in 2018 a predator was about to bring destruction to their lives.

Cimarron took her own life rather than comply with McCartney’s depraved demands that she include her younger sister in the abuse.

Her father, Ben, a US army veteran, killed himself 18 months later not knowing what had caused his daughter’s death.

In 2021, just before McCartney was due to be arraigned on charges, investigators discovered Cimarron’s identity and what had happened to her.

McCartney was ultimately charged with her manslaughter – a charge he pleaded guilty to earlier this year.

You can read more about Cimarron here.

Image source, Family handout

Luke Sproule
BBC News NI at Belfast Crown Court

McCartney has been handcuffed and led out of the dock by the custody officers.

Luke Sproule
BBC News NI at Belfast Crown Court

McCartney has sat with his head bowed throughout today’s hearing.

He did not react as the judge sentenced him.

The judge has also imposed a sexual offences prevention order.

McCartney kept his eyes closed as he stood to hear his sentence but showed no other emotion.

Alexander McCartney has been sentenced to life in prison and must serve a minimum of 20 years.

Police have released this new custody photo of Alexander McCartney.

Image source, Police Service of Northern Ireland

Luke Sproule
BBC News NI at Belfast Crown Court

Before imposing his sentence, the judge said the offending was of the most serious type and there is also a likelihood of McCartney offending again.

“I do not sense remorse or shame,” he said.

Alexander McCartney has been handed a life sentence with a minimum of 20 years.

The judge says because he has already served five years in custody, McCartney will not be eligible for release until 2039

Alexander McCartney has been sentenced to life with a minimum of 20 years.

Luke Sproule
BBC News NI at Belfast Crown Court

The judge asks the defendant what confidence anyone can have after carrying out this scale of abuse against children for many years.

The judge notes that the fact McCartney is young means he can change, but it also increases the risk of reoffending if he does not change.

Luke Sproule
BBC News NI at Belfast Crown Court

The judge says the defendant has used social media on an industrial scale, was remorseless, ignored multiple pleas for mercy, lied and acted for his own sexual pleasure.

He says it is hard to think of “a sexual deviant who poses more risk than this defendant”.

Luke Sproule
BBC News NI at Belfast Crown Court

Mr Justice O'Hara is now setting out mitigating and aggravating factors.

He says McCartney has now shown some remorse, but he notes that this has only come after five years in custody and was absent before 2019.

He notes a number of aggravating factors including the number of victims, their age, the way images were saved and sorted and McCartney's “complete indifference to the impact of his actions”.

Luke Sproule
BBC News NI at Belfast Crown Court

The judge returns to the fact McCartney has consistently said he was a victim of catfishing.

He says on the balance of probabilities McCartney has not provided evidence for this.

He says even if he is wrong in this, it would provide limited mitigation in this case.

Luke Sproule
BBC News NI at Belfast Crown Court

The judge says that McCartney said he wanted to see how hard he could push his victims and how far he could control them.

He adds that in interviews he never referred to “children” or a “child”, preferring to pretend his victims were not real.

Luke Sproule
BBC News NI at Belfast Crown Court

The judge is now addressing McCartney, who he says began offending at the age of 14.

“He started young and once he got going it got worse and worse,” the judge says.

He adds that the defendant had a “happy childhood” and had no previous convictions.

Luke Sproule
BBC News NI at Belfast Crown Court

We are now hearing victim impact statements - the opportunity for victims of crimes to share with the court and the judge how a crime has affected them ahead of sentencing.

The judge says they make for gruesome reading and the impacts include stress, shame, a loss of trust and for many victims their childhoods had been stolen.

Some have attempted suicide and others have endured suicidal thoughts.

Luke Sproule
BBC News NI at Belfast Crown Court

We are now hearing details about the abuse suffered by a 12-year-old girl who shot herself after being catfished by McCartney.

After being abused by McCartney she told him she was going to kill herself, to which he replied “good luck and goodbye”.

The judge says that no matter what McCartney said later, it is clear he was “absolutely devoid of empathy or remorse at the time”.

Luke Sproule
BBC News NI at Belfast Crown Court

Mr Justice O’Hara outlines the account McCartney gave to police which included that he had been catfished himself.

The judge says this account was dishonest and there’s no evidence he was catfished.

He says McCartney had prepared the account in the event he was arrested.

Luke Sproule
BBC News NI at Belfast Crown Court

The judge refers to the prosecution, who said there was “an escalation in McCartney's conduct as time went on” as “the depravity of his conduct increased”.

Mr Justice O'Hara cites a case where a victim sent him a message saying she thought she was going to die.

McCartney replied: “I don’t care."

Luke Sproule
BBC News NI at Belfast Crown Court

Mr Justice O'Hara says victims often cried and told McCartney they were terrified.

Some told him they would kill themselves or showed him images of self harm.

McCartney's responses, the judge says, were “devoid of normal human empathy”.

Luke Sproule
BBC News NI at Belfast Crown Court

The judge says McCartney found ways to “degrade and humiliate” his victims.

He sets out some of the ways in which he did this - which are too graphic for us to report.

Luke Sproule
BBC News NI at Belfast Crown Court

The judge says McCartney would often tell his victims that if they complied with his demands he would delete their photos once the ordeal was over.

However, when police searched his devices, they found images which he had not deleted.