The gangs created social media accounts on which they posed as attractive Asian women and befriended victims.
The fraudsters invited victims to engage in cybersex activities via webcam, during which the woman would take off her clothes to entice the victim to take off his.
He also admitted making 36 Category B images and 197 in Category C.
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A total of HK$2.6 million was pocketed by swindlers through sextortion, compared to HK$1.6 million over the same period in 2014.
Lin said most of the scams were operated by syndicates in Southeast Asia.
In May last year Branney was given a suspended jail sentence after he admitted possessing and making indecent images of children and possessing extreme animal porn.