Man sentenced over internet blackmail

A 29-year-old man who posed online as a teenage boy to blackmail seven underage girls into sending him explicit images and videos of themselves has been given a suspended jail sentence.

In the South Australian District Court Trevor Phillip Harris pleaded guilty to 10 counts of using a carriage service to menace, harass or cause offence, two counts of soliciting child pornography and one count of transmitting child porn.

Harris used Skype and social media to get sexually suggestive or explicit photographs and videos from the teenage girls and threatened to post them online unless they continued to send him more material.

In some instances he demanded the girls perform sex acts.

Passing sentence Judge Sydney Tilmouth told Harris his behaviour from June 2011 to August 2013 was manipulative, aggressive and threatening.

Harris who claimed he was 17, sent 61 emails including 22 that included specific threats.

"These contained threats to disseminate sexual images of them (the girls) should they fail to comply with your repeated demands to send further images and videos," Judge Tilmouth said in a judgment published online on Monday.

The judge imposed a sentence of two years and nine months, but suspended the term, placing Harris on a two-year good behaviour bond despite "little discernible evidence of remorse or regret".

He also ordered Harris not to access Skype or any internet chat rooms.