The convicts are Prosenjit Gain, husband of the victim, Onimesh Gain and Biplob Kanti Mandal.
The court also sentenced them to seven-year jail e a ch and fined Tk 45,000 under two other sections.
According to prosecution, Tumpa was choked to death by her husband on October 7, 2016 and her body was dumped in Ghangrail River.
Police recovered her body two days later.
Her brother filed a case against Somit Mandal filed a case with Dumuria Police Station in this connection.
Police submitted chargesheet against four accused on November 25, 2017.
After examining all these records and 26 witnesses among 28, Khulna district and sessions judge Moshiur Rahman Chowdhury handed down the verdict acquitting one accused.
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