'Appalling': 50 schoolgirls targeted with AI fake nudes

A teenager has been arrested after explicit images of pupils at a Melbourne school circulated online.

Fifty girls in years nine to 12 at Bacchus Marsh Grammar, northwest of the city, had manipulated images shared, according to principal Andrew Neal.

"It's appalling. It is something that strikes to the heart of students, particularly girls growing up at this age," Mr Neal said in a statement to the ABC.

"They should be able to learn and go about their business without this kind of nonsense."

Mr Neal said images of pupils' faces were taken from social media before being manipulated using AI to make "obscene photographs".

A Victoria Police spokeswoman said the arrested teen was released pending further inquiries, but the investigation was ongoing.

Officers were told images were sent to a person in the Melton area via an online platform on Friday, June 7, she said.

Bacchus Marsh Grammar, 50km northwest of Melbourne's CBD, has more than 2300 pupils across three campuses.