Warning: Graphic content
A Cambridge University scientist led a double life blackmailing victims including children into sending him severe abuse images of themselves and sharing them on the dark web.
Dr Matthew Falder, 28, who was arrested at Birmingham University where he worked, posed as a female artist on sites such as Gumtree to trick his victims into sending him naked or partially-clothed images of themselves, The Telegraph UK reports.
Falder, whose crimes make him one of Britain's most prolific sex offenders, would then blackmail them into sending increasingly degrading images of themselves, targeting more than 50 victims and leaving some so devastated they attempted suicide.
He then distributed the images using the names "666devil" and "evilmind", including some which showed babies and children being tortured, on the dark web, and discussed them at length to humiliate and degrade the people who were the subject of the pictures.
The investigation, led by the National Crime Agency, is believed to be the first prosecution in the UK of "hurt core" where offenders use hidden web forums dedicated to the discussion of and video sharing of rape, murder, sadism, torture, paedophilia, blackmail, humiliation and degradation.
His father Stephen Falder told Sky News: "This has turned our lives upside down. It came as a complete shock and the family is totally devastated."
Falder was seen as the life and soul of the party at Cambridge University when his offending began around 2010.
He was eventually unmasked by spies from GCHQ and arrested at Birmingham University where he was working as a postdoctoral researcher in June.
The geophysicist, who was living with his girlfriend, has now pleaded guilty to 137 offences, including causing the sexual exploitation of a child, voyeurism, making and distributing indecent images of children and encouraging the rape of a 4-year-old.
He also set up secret cameras to film people he knew in the shower.
Ruona Iguyovwe, from the Crown Prosecution Service's International Justice and Organised Crime Division, said: "Matthew Falder is a highly manipulative individual who used his knowledge of computers and the internet to persuade dozens of young people to supply him with degrading images he could distribute online and subsequently use in blackmailing them.
"He clearly enjoyed humiliating his victims and the impact of his offending, which carried on over several years, has been significant."
Matt Sutton, National Crime Agency senior investigating officer, said: "In 30 years of law enforcement I have never come across such horrifying offending where the offender's sole aim was to cause such pain and distress.
"There are more than 50 victims in this case and I commend them for their bravery in helping us convict a truly evil offender.
"It has been an extremely complex investigation into a prolific online predator, who over several years believed he could evade law enforcement to sexually and sadistically exploit vulnerable victims."
Falder, of Edgbaston, Birmingham, was remanded into custody until December 7, when he will be sentenced at Birmingham Crown Court.
The University of Cambridge, which confirmed Falder was a student until 2016, said that it was "shocked and saddened" by the case.
A spokesman for the University of Birmingham said: "The university is shocked to hear of the abhorrent crimes committed by a former post-doctoral researcher."
WHERE TO GET HELP:
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