A Class 12 student, above 18, was arrested today for starting "Bois Locker Room", an Instagram group on which obscene messages and morphed photos of underage girls were shared. The teen studies in a Noida school and sat for the Class 12 exams this year.
Fifteen more students of prominent Delhi schools have been questioned and their phones have been seized.
The police have identified 27 members of the group - some were underage and some 18 and older.
Sources say the students mostly claimed that they did not know much about the group and they had been added to it by others.
The chatroom, exposed on Sunday by a girl targeted in the grisly group chats, has drawn massive anger, shock and disgust on social media. Class 11 and 12 students casually discussed "gang-raping" girls, sexualized and slut-shamed them in screenshots of chats that have gone viral on Twitter and other social media forums.
It is believed that some of the participants were as young as 13, which has seeded a debate on toxic masculinity and objectification of girls starting in schools and the need for greater control over the internet activity of children.
In a statement, Facebook-owned Instagram said it gave top priority to ensuring its users can express themselves in a "safe and respectful way".
"We absolutely do not allow behaviour that promotes sexual violence or exploits anyone, especially women and young people, and have actioned content violating our Community Standards as we were made aware of it," a Facebook spokesperson said.
The company said the objectionable content that violated its community standards was removed as soon as it was made aware of it.