Nawshin had passed the SSC this year with GPA-5.

Her autopsy report submitted yesterday morning stated that there was no sign of attack or injury to the body and the cause of death was suicide, forensic department sources said.

Police could not make any headway in the investigation without details of the victim and the prime suspect, victim's maternal uncle, as the victim's parents are still not available for questioning.

Nawshin's parents left for their village home in Pirojpur on Thursday for her burial.

Police have been conducting raids at possible hideouts in the capital to capture the prime accused in the case -- Zahidul Haque Rintu, Nawshin's uncle.

The other accused in the case, Shajahan Mia, security guard of the building, was arrested on Thursday and taken on a two-day remand on Friday. He, however, could not provide any substantial information regarding the incident, police sources said.

"We are yet to receive the autopsy report," said AKM Daulat Akbar, officer in charge of Ramna Police Station adding, "We cannot make any comment about the investigation as Nawshin's parents are yet to return. We need to interrogate them further for details."

On Thursday, Nawshin's father Sultan Faruk, an accountant of Bangladesh Rifles (BDR), filed the case with Ramna Police Station accusing his brother-in-law Zahidul Haque Rintu as the prime suspect.