A Russian national died after an altercation involving two Russian nationals at the Green City residential complex in Ruppur, Ishwardi, on 3 August.
The second man was hospitalized with serious injuries.
Both men were described as workers connected to a Russian contractor on the Ruppur nuclear power project.
Police and local residents said the two men had been drinking before an argument developed into a physical altercation.
They said both men sustained serious injuries and were taken for medical care.
The circumstances of the death have not been publicly established, and accounts differ on whether the man died during transfer or while receiving treatment.
Ishwardi police chief Md Asadur Rahman said the body was sent for a post-mortem examination.
He said the investigation and post-mortem findings would be needed to determine the cause of death.
Rahman said legal procedures were under way.
Police said arrangements would be made through the Russian embassy to hand over the body to relatives after required procedures are completed.