What crime did she commit?

Shah Nurul Afsar, Londoni Road, West Subidbazar, Sylhet
I am working as Second Officer of Bangladesh Krishi Bank, Biswamborpur Branch, Sunamgonj. My eldest daughter Ferdousi Rumman Rimu was a student of B.Com (Hons) Third year in the Accounting Department of Modanmohon College, Sylhet. On December 05, 2007 she left the house for college at about 10.00am. Till then she was missing. Later we were informed over mobile by Mr. Abdul Hye, Officer-in-Charge, Bishwanath Thana, Sylhet about a dead body of a girl (by retrieving mobile number from a SIM found from her purse). They also informed us that the dead body was already handed over to Anjuman Mofidul Islam, Sylhet. In the mean time, Anjuman Mofidul Islam had buried the dead body in their graveyard. I am that ill-fated father who couldn't see the face of my beloved daughter. To fulfil my daughter's desire to complete higher education, I sent her to Sylhet but failed to protect her life. This news was published in different national and local dailies. I wonder for what reason such a devastating event happened to my family. Why did the culprits kill my beloved daughter? I seek the cooperation of all concerned in identifying the killers and bring them to justice.