A “sadistic” paedophile who exploited and blackmailed almost 2,000 victims globally after posing as an online sugar daddy has admitted 158 charges in what has been described as “industrial-scale” offending.

Abdul Elahi, 26, admitted a host of charges – thought to be among the highest number of offences one individual has ever pleaded guilty to – after a lengthy investigation, the National Crime Agency (NCA) said.

Elahi had previously admitted a majority of the offences, but pleaded guilty to the final tranche of allegations at Birmingham Crown Court last month.

He will be sentenced at a later date.

Elahi’s pleas could only be reported on Monday after reporting restrictions were lifted.

His offending included blackmailing victims into sending him humiliating and degrading videos and images of themselves, children and siblings which he then sold online, the NCA said in a statement released following Elahi’s admissions.

He also provided online classes on the encrypted Telegram app, teaching would-be abusers how to blackmail victims and obtain indecent images.

Unemployed Elahi, formerly of Allcroft Road, Sparkhill, in Birmingham, operated by pretending to be a stockbroker or rich businessman on sugar daddy websites.

He then singled out victims who were in debt or too young to legitimately be on the sites, tricking them into sending naked or partially clothed images of themselves.

The investigation team have been horrified by Elahi’s sadistic depravity and the industrial scale of his offending

Elahi also targeted some victims on social media.

He promised payment of thousands of pounds for posed images and sent fake screenshots of money leaving his account in similar transactions to convince victims.

The NCA uncovered evidence of at least 196 victims in the UK, and contacts with up to 600 more online.

Elahi had also tried to contact 1,367 women in the United States, with victims in 20 other countries including Australia, Canada and New Zealand.

The NCA worked across borders with international law enforcement to safeguard people Elahi had contacted.

After a short time, Elahi moved victims onto the WhatsApp messaging app and away from the websites where he first met them.

Once he had secured enough revealing images, he would then threaten to expose the photos to victims’ families and friends unless they sent more.

Elahi then made some victims abuse themselves, including self-mutilation, blackmailing women to send footage of themselves abusing young children and making girls abuse siblings.

Investigators said many of the victims were so terrified they felt they had no choice but to comply, with some “goaded” to contemplate suicide.

Once he had images, Elahi systematically categorised them into box sets, held in cloud storage sites, which he then sold as collections via Telegram, making more than £25,000.

The move heaped further misery on victims, as family and friends became aware, and more offenders tried to blackmail them.

Elahi was snared in December 2018 by NCA agents, after an allegation he was blackmailing a teenage girl in the United States.

His mobile phone and computers were seized and forensically examined, leading investigators to uncover his “industrial-scale” offending.

Elahi admitted offences against a total of 79 victims, ranging from children aged under one to adults, carried out between January 2017 and August 2020.

They included multiple counts of blackmail, disclosing private sexual films and photographs to cause distress, making and distributing indecent images of children, encouraging the sexual assault of children, sexually assaulting a boy, causing or inciting children to engage in sexual activity, fraud and possessing more than 65,000 indecent images of children.

The NCA said that where children could be identified, they had been safeguarded.

Sophie Mortimer, of the Revenge Porn Helpline, said they had worked successfully to remove thousands of images generated by Elahi’s offending from websites but that “this work will continue for many months”.

She added it was some of “the most extreme” content the helpline had dealt with and had had a “life-changing” impact on many victims.

Tony Cook, the NCA’s head of child sexual abuse investigation operations, said: “The investigation team have been horrified by Elahi’s sadistic depravity and the industrial scale of his offending.”

Commending the bravery of the victims, he added: “Elahi has displayed zero empathy.

“He often goaded them to the point of wanting to kill themselves.”

He urged parents to speak with their children about who they talk to online, adding investigations stemming from Elahi’s offending were continuing.

The crimes that Elahi committed worldwide were horrifying and sadistic. The extent of the offences is almost unheard of

Sarah Ingram, Crown Prosecution Service specialist prosecutor, said: “The crimes that Elahi committed worldwide were horrifying and sadistic.”

“The extent of the offences is almost unheard of,” she added.

“This level of depravity is shocking and will impact the victims for their whole lives.”

A second defendant, Kirsty Elizabeth Nicholls, 35, of Northolt, Middlesex, also admitted offences.

Nicholls knew Elahi from a sugar daddy website and together they admitted two sexual assaults against a child and both admitted making indecent images of the child.