A Northern Ireland man who catfished more than 70 children online targeted victims "who were gay or exploring their sexuality", a Belfast court has heard.
Warning: This article contains details readers may find distressing
Alexander McCartney, 26, is awaiting sentencing after pleading guilty to 185 charges, including the manslaughter of a 12-year-old American girl who took her own life.
A pre-sentence hearing was told his victims were aged between 10 and 16 and located in the UK, USA, continental Europe, Australia and New Zealand.
Using a fake identity on social media, he persuaded them to send him images, then used these to blackmail them into sending more graphic material.
David McDowell KC, the prosecution barrister, said McCartney, from County Armagh, had "degraded and humiliated them" and "the harm he has caused is unquantifiable".
The former computer student pleaded guilty to one count of manslaughter, 59 of blackmail, and 70 of inciting a child to engage in sexual activity.
He further admitted dozens of charges related to the making and distribution of indecent images of children, and appeared "utterly remorseless", according to the prosecution.
The law in Northern Ireland prohibits the naming of the child who died by suicide after McCartney had threatened to post images of her online.
Read more from Sky News:
Former One Direction star dies aged 31
David Cameron opens up about son's death
Olympian guilty of raping teenage girls
The court heard he had "counted down" online, from 20 to zero, demanding more pictures from her, before she shot herself with her father's gun.
McCartney, dressed in a black, white and grey sweatshirt, sat with his head in his hands, looking only at the floor throughout the pre-sentence hearing.
Described in court as "the UK's largest catfishing case", the global investigation was launched when Police Scotland received a report of attempted blackmail on Snapchat.
When police searched McCartney's rural home, they found thousands of images of young girls "in various states of dress and undress, performing various sexual acts".
:: 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: Northern Ireland man catfished more than 70 children globally - including 12-year-ol
How Israel found and killed Hamas leader Yahya Sinwar
Israel has removed one of its biggest foes - Yahya Sinwar's death brings forward the opportunity to start to end its war in Gaza
One Direction bandmates react to Liam Payne's death saying they are 'completely devastated'
Liam Payne's close friend reveals final messages singer sent her hours before his death
