"The letter was sent to forensic lab for handwriting match and other analysis. It would take a few days to get the report", said police.
Rohith's body was found hanging at one of the hostel rooms on the University of Hyderabad campus on Sunday.
Rohith and four other students were earlier suspended from the university following an alleged assault on an ABVP leader. Later, the suspension was revoked but they were barred from accessing hostel facilities.
When contacted, Inspector J Ramesh of Gachibowli police refused to share any information saying it would hamper the investigation.
Cyberabad police has named Labour Minister Bandaru Dattatreya, Vice Chancellor Appa Rao, Telangana BJP MLC Ramachandra Rao and two students in the FIR filed in the suicide case.

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