Overseas criminals are extorting money off teenage Australian boys by tricking them into sending sexually explicit images online.
Kids Helpline data, released on Monday, shows 78 per cent of children contacting the service about sexual extortion - or sextortion - in the past five years were boys aged between 14 and 17.
Girls were previously the most common group contacting the service over the blackmail attempts, said Tracy Adams, the chief executive of Kids Helpline provider yourtown.
"Victims often feel like they are powerless to do anything to prevent the release of the images they have shared and feel they will be deeply shamed and embarrassed," she said.
"This has an obvious impact on their mental health and wellbeing."
Some boys reported the criminals threatened to release their intimate images online if they didn't hand over thousands of dollars, Ms Adams said.
This kind of blackmail was becoming increasingly common with overseas organised crime syndicates often behind the demands, Australian Federal Police acting commander Jayne Crossling said.
"This is a global phenomena," she told the ABC.
"Those typical syndicates have been scamming adults for decades now, they've just now decided to pivot because they can see there's perhaps some money to be made on young people."
But it was unclear why young boys were being targeted more than girls, Ms Crossling said.
"We believe there's some element that perhaps they are more likely to pay to make the problem go away," she said.
"Right now, about 94 per cent of the victim reports that we're receiving are boys."
Blackmail victims should report the incident to eSafety Australia or the police if they were concerned about their physical safety, Ms Crossling said.
They should not send any money or further photos in the interim, and stop all contact with the blackmailer.
Services such as Kids Helpline were also available to help with the mental toll, Ms Adams said.
"If your child is or has been a victim, it is important to stay calm and reassure them that it's not their fault and that there is help available," she said.
Young people can access Kids Helpline either online or on 1800 55 1800.
Lifeline 13 11 14
Kids Helpline 1800 55 1800 (for people aged 5 to 25)
