The inferno at the BM Inland Container Depot, a Dutch-Bangladesh joint venture, broke out around midnight Saturday following explosions in a container full of chemicals.
The cause of the fire could not be immediately determined. The depot is located near country's main Chittagong Seaport, 216 kilometres southeast of the capital, Dhaka.
At least nine firefighters were among the dead, according to Brigadier General Main Uddin, director general of the Bangladesh fire service and civil defense. More than 10 others were being treated for burns, he added.
Multiple rounds of explosions occurred after the initial blast as the fire continued to spread, Uddin said. Explosives experts from Bangladesh's military have been called in to assist the firefighters. The explosions shattered the windows of nearby buildings and were felt as far as four kilometres away, officials and local media reports said.
The death toll reached 49 by Sunday evening, according to Ekattor TV station, and the area's civil surgeon said the number could still rise as the fire raged for a second night.
Prime Minister Sheikh Hasina expressed her shock at the accident and ordered adequate arrangement for medical treatment of the injured.
Bangladesh has a history of industrial disasters, including factories catching fire with workers trapped inside. Monitoring groups have blamed corruption and lax enforcement.
Global brands, which employ tens of thousands of low-paid workers in Bangladesh, have come under fire to improve factory conditions in recent years. In the country's massive garment industry, which employs about four million people, safety conditions have improved significantly after massive reforms, but experts say accidents could still occur if other sectors do not make similar changes.
In 2012, about 117 workers died when they were trapped behind locked exits in a garment factory in Dhaka.
The country’s worst industrial disaster occurred the following year, when the Rana Plaza garment factory outside Dhaka collapsed, killing more than 1,100 people.
In 2019, a blaze ripped through a 400-year-old area cramped with apartments, shops and warehouses in the oldest part of Dhaka and killed at least 67 people. Another fire in Old Dhaka in a house illegally storing chemicals killed at least 123 people in 2010.
In 2021, a fire at a food and beverage factory outside Dhaka killed at least 52 people, many of whom were trapped inside by an illegally locked door.