Four workers sustained burn injuries in an explosion at a rolling mill in Rupganj, Narayanganj, on Wednesday night.
The incident occurred at Premier Steel Mill in Ariab area of the upazila at around 9:30PM.
The injured workers were identified as Abir, Nabir, Nazmul and Rakib.
They were initially taken to a local hospital, later, shifted to the National Burn and Plastic Surgery Institute in Dhaka in critical condition.
Abir is said to be in critical condition.
The workers said a loud explosion suddenly occurred while they were working inside the mill on Wednesday night. Four workers suffered burn wounds in the incident.
On receiving the information, a unit of Kanchan Fire Service visited the scene.
Abdullah Al Arifin, deputy assistant director of the Fire Service, said they initially suspected that the accident occurred due to the release of molten metal.
However, the actual cause of the explosion will be known after an investigation, he added.
EM/TF