Law enforcement officers are worried about fake celebrity accounts who are speaking inappropriately to young children, and they're becoming more difficult to police.
A detective specialising in targeting child exploitation told the BBC that the problem is getting worse.
"Identity assumption by child sex offenders is increasing quite steadily," Queensland Detective Inspector Jon Rouse said.
As social media sites and apps continue to expand, it becomes more difficult to police fake social media accounts.
An unnamed parent also spoke to the BBC, telling them that a fake celebrity account had asked her eight-year-old daughter to send them naked photos, in order to win a chat with the celebrity.
"The fact that so many children across the world could believe that they were talking to Justin Bieber, and that Justin Bieber would make them do the things that they did, is really quite concerning," Det Insp Rouse said.
He's calling for more education for children about safe online behaviour, and says that young children may be less likely to recognise that official accounts have verified logos.
One account, called @PrvtHarryStyles was pretending to be Harry Styles and asking young people to send pictures.
Twitter has since closed the account down, along with a fake Instagram account run by the same person, according to the BBC.