Matthew Falder, 28, who dubbed himself "666devil" and "evilmind" online, blackmailed many of his 50 victims into sending "severe abuse images" of themselves.
Falder, whose victims ranged from young children to people in their 30s, would pose as a woman and get his victims to send naked images. He would then manipulate them into sending increasingly depraved abuse images.
"The purpose was to humiliate and degrade the victims," the NCA said.
Falder, a geophysicist, admitted the charges at a court hearing in Birmingham, central England, making him one of Britain's most prolific sex offenders.
"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 is a graduate of Cambridge University and was a postdoctoral researcher at Birmingham University.
(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)
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