The body of Abrar Fahad, 21, was found in a dormitory days after he posted comments criticising the government.
Several members of the student wing of the governing Awami League have been detained in connection with the death.
The killing has shocked Bangladesh and shone a light on the culture of violence in public universities.
The Bangladesh Chhatra League (BCL), the student wing of the Awami League, has been widely accused of using torture and extortion against students.
The government has promised to bring those responsible for Abrar Fahad's death to justice.
His body was found on Sunday at the Bangladesh University of Engineering and Technology (Buet) in the capital, Dhaka.