The convicted are – Lelin Bapari and Rezaul Bapari of Dhusha village in Kalkini upazila, Shahbuddin Dorji of Kukuril village, and MM Faisal Ahmed of Thantoli village. Rezaul is absconding.
A sixth accused, Mohiuddin Darji, was acquitted.
Speedy Trial Tribunal-3 judge Monir Kamal also fined the convicts TK 20,000 each. They will have to stay in jail for two more months if they fail to pay the fine.
Wahiduzzaman was an MA student at Madaripur Government Nazimuddin University College and a part-time employee of The Hunger Project, an international volunteer organisation.
According to the prosecutions, Wahiduzzaman, son of Mozammel Hossain of Singair upazila, gave Tk 10 lakh to Rezaul to go to Italy. But Wahiduzzaman failed to go abroad and asked the convict to give back his money, leading to an altercation.
Mohiuddin and Rezaul planned to kill the student instead of giving back his money. According to their plan, Shahbuddin, Lelin and Selim asked Wahiduzzaman to come to Savar to take money from them on March 6, 2013.
When Wahiduzzaman reached Savar, the convicts took him to a maize field and strangled him to death.
Lelin, Shahbuddin, Selim, Faisal were directly involved in this murder, according to the charge sheet.
Selim died during the trial proceedings.
Sub-Inspector Salam of Singair Police Station filed a murder case over the killing. Later, Detective Branch Inspector Madon Mohon pressed charges in court against six people on November 22, 2014.
The court indicted them on November 27, 2016. Twenty-two witnesses testified in the case.