Buet student Abrar Fahad died of internal bleeding after he was beaten mercilessly with blunt objects, said doctors at Dhaka Medical College Hospital after an autopsy.
"The body had extensive bruises and he died of internal bleeding, said Sohel Mahmud, a physician at the hospital.
He conducted Abrar's autopsy around 1:30pm on Monday.
Later, the head of forensic medicine department of the hospital briefed the media.
"The boy was heartlessly beaten to death," said Sohel Mahmud.
Abrar, a second year student of the Bangladesh University of Engineering and Technology (Buet), was found dead at Buet dormitory in the wee hours of Monday.
Activists of Buet chapter Chhatra League allegedly beaten the student to death over a Facebook post. Abrar in his last post was critical of Bangladesh-India relationship.
Centring this, his batch-mates called Abrar outside of his room on Sunday evening.
He was allegedly tortured to death at a room of the dorm. His body was then dumped on the staircase.
Abrar's cousin Abu Talha was present at the Dhaka Medical College Hospital and claimed that Chhatra League leaders and activists picked his brother from his room and murdered him cold-bloodedly.