Sources said the fire broke out at a factory of KTS, a composite textile mill of Arina Group, at BSCIC Industrial Area in Kalurghat at around 7:20pm.

The fire originated from an unknown source soon engulfed the entire four-storey building. Sources and witnesses said bamboos and woods used in an under construction part of the building fuelled the blazes.

Twenty fire tenders rushed to the scene and rescued around 100 victims, some of whom severely burned, with the help of locals and pedestrians.

At least 60 were rushed to Chittagong Medical College and Hospital (CMCH) and three of them died on the way, sources said. Firefighters pulled the charred bodies of others out of the ashes.

"All the dead are women," said CMCH Resident Surgeon Matiar Rahman Khan, adding, "No-one of them could be identified immediately."

The injured alleged most of the workers were trapped in the inferno as authorities locked one of the two exits of the building.

"Many of us had to get out of the building using ropes, bamboos and other construction materials. But most of our female colleagues could not follow us and were trapped inside," Hasan, an injured worker, told The Daily Star. His colleague Jahid, 18, echoed him at the CMCH.

"Some of us suffered injuries jumping out of the windows or making hurried efforts to come out through a narrow staircase that was fortunately open," said another worker, Delwar Hossain, of Pabna.

"The situation could have been worse had it not been the time for changing shifts, as many workers had already left for home," said an injured Siraj, who along with his colleagues was working on the 8:00am-to-6:30pm shift.

The sources said about 500 people work in each shift of the factory.

Hospital sources said 40 workers were released after receiving first aid. Rescue operation continued until 11:15pm last night.

The firefighters were desperately trying to bring the fire under control by then, sources said.

Meanwhile, a fire last night injured six employees of Kushiara Rubber Sole Factory at Lalbagh in the city, reports our staff correspondent in Dhaka.

Firefighters doused the flames at 11:00pm after three hours of struggle. The fire originated from a candle that the employees lit during load shedding, witnesses said.

The injured, one was stated to be in a critical condition, were rushed to Dhaka Medical College and Hospital.