Y Suresh Babu, M Bhanu Prakash and M Hemanth, all third-year engineering students at a private institute in Dundigal, were absconding after the incident on Friday.
The trio allegedly assaulted one Shravan Kumar, who is pursuing pharmacy course at the same institute, during a ragging session, they said.
Reportedly depressed over the harassment and assault, Kumar consumed some tablets in a bid to end his life. He was admitted to a hospital, where his health condition is improving, police said.