A man was killed and three others were injured in an explosion at the evidence room of Jhenaidah Chief Judicial Magistrate Court around 1:30pm on Sunday.
The deceased was identified as Shafiqul Islam, an electrician. The injured were admitted to Jhenaidah Sadar Hospital.
However, the police and fire service are yet to find out the cause of the blast.
Shamimul Islam, deputy assistant director of the Jhenaidah Fire Service, said electricians from the public works department were working there.
"Suddenly the people present in the court heard a loud explosion and came running. The doors and windows of the evidence room were broken and a fire broke out inside," he told The Business Standard.
The fire service reached the spot and brought the fire under control.
Later, four injured people were rescued from the room and admitted to Jhenaidah Sadar Hospital, where Shafiqul succumbed to his injuries.
Jhenaidah Sadar Hospital Supervisor Dr Harun Aur Rashid said one died after being brought to the hospital. "One left with first aid and two others are being treated at the hospital," he added.