The condemned convicts are Sujon Talukdar, 24, son of Abdul Kader Talukdar, Saiful Islam, 22, son of Mujibur Rahman and Dulal Madbor, 22, son of Manan Madbar of Charsundi village in sadar upazila.
District Women and Children Repression Prevention Tribunal Judge Abdus Salam Khan passed the order.
According to the case statement, Samsun NaharTanu, wife of Ishak Molla of Baluchara village in the upazila, left her house on August 17 in 2014 for her tuition.
On her way, Saiful and Dulal picked her up and took her to different places where they violated the woman along with another convict Sujon.
On August 18, they killed the woman and concealed the body in a ditch.
On August 22, police recovered the body from the ditch. A murder case was filed in this connection.