Bacchus Marsh Grammar School, a private school, reported that artificial intelligence was used to manipulate photos of its students into "obscene" and "incredibly graphic" material, which was then distributed on Instagram and Snapchat earlier this week.
The altered images were made with photos taken from the social media profiles of the female students in the upper grades, according to The Independent.
Police were informed that several of these images were transmitted to an individual in the Melton area, a suburb on the outskirts of Melbourne, through an online platform on June 7, before it was shared.
Authorities have detained a teenager connected to the distribution of these explicit images online.
He has been released while further investigations are ongoing.
About 50 girls at the school were included in the deepfake images, according to the school and the police.
School principal Andrew Neal described the situation as "appalling".
"It is something that strikes to the heart of students, particularly girls growing up at this age," he told ABC News.
"Logic would suggest that the most probable suspect is someone from the school," said Neal.
However, he added that the police and the school were not dismissing any other possibilities.
A parent named Emily, whose daughter goes to Bacchus Marsh Grammar School, told ABC that she had seen the images and described them as "incredibly graphic."
She said her daughter, whose image did not appear in the deepfake photos, was very upset and was throwing up in response to the images.