Firefighting official Abdullah Al Arefin made this known on Friday.
Firefighters took nearly 20 hours to extinguish the blaze that broke out at the six-storey factory building of Hashem Food and Beverage Limited owned by Sajeeb Group on Thursday afternoon.
Arefin said the bodies of 49 workers were found on the fourth floor of the building.
A search operation is about to be conducted on the fifth and sixth floors, he added.
Three workers had been found dead on Thursday after the fire broke out at the factory, located nearly 25km east of Dhaka.
The factory was manufacturing juices, soft drinks and other food items.
Arefin said emergency forces rescued at least 25 workers who were able to reach the rooftop soon after the fire broke out.
But the fourth floor was padlocked, trapping the workers there to die.
Workers who survived told broadcasters that the gate was padlocked for security reasons, and security guards refused to open it without the owner’s orders.
“We could have saved them, had they reached up to the rooftop,’’ Arefin said, adding that the fire engulfed the entire building, preventing rescue services from entering it in the initial hours of the operation.
Police officer Zayedul Alam said many workers managed to escape the blaze on their own.
Television footage showed survivours saying they broke open another padlocked gate to escape the blaze soon after they heard the fire alarm.
At least 1,000 employees were inside the factory when the fire broke out, they said.
Flammable materials piled up inside the building – including foil paper, resin, plastic bottles, oil and paper – intensified the blaze, according to Arefin.
The reason for the fire was however not clear yet, said Mostain Billah, chief administrator of the district.
No official from the factory was available for comment.