A student at Jadavpur University and two former students were arrested on Friday night in connection with the death of the first-year student.
One of the nine accused arrested earlier in the case was taken to JU Main Hostel on Friday for a “reconstruction” of the events that could have led to the death of the 17-year-old.
The first-year student was allegedly ragged and thrown from a second-floor balcony of the main hostel on the night of August 9.
The three who were arrested on Friday are Sheikh Nasim Akhtar, Himanshu Karmakar and Satyabrata Roy, police said.
Roy is a fourth-year student of computer science engineering. Akhtar studied chemistry and Karmakar mathematics at JU.
The police said Akhtar is from Memari in East Burdwan, Karmakar from Shamsherganj in Murshidabad and Roy from Haringhata in Nadia.
Officers said all three were present in the hostel on the night of August 9 and are suspected to be involved in the events that led to the death.
Roy, an officer said, had called the dean of students, Rajat Roy, at 10.05pm on August 9 apparently to inform him about a student being “politicised” in the hostel.
The police said they are trying to verify whether Roy had just informed the dean about a student being “politicised” or also spoke about any incident of ragging.
Saptak Kamilya, a former student and one of the nine accused arrested earlier, was taken to the main hostel on Friday afternoon.
“He was taken to the second and third floors and to all the rooms where the victim was taken on the night of August 9,” said an investigator.