On Monday morning, the 17-year-old told her friends that she would go to school late. She did not reach school even after an hour. A few staff members checked her hostel room and found her hanging from the ceiling.
Her body was sent to Government Hospital in Tiruvallur for postmortem. Police said the girl had been upset for the past three days and had not mingled with her friends.
A case that was registered by Mappedu police has been transferred to the CB-CID.