At least 16 people have died after a huge fire broke out at a garment factory in Bangladesh, with officials warning that the toll could rise.

Sixteen bodies have been recovered and would be handed to families after DNA testing, as they have been burnt beyond recognition, the fire service said.

Distraught relatives gathered outside the four-storey factory in Dhaka's Mirpur area on Tuesday in search of their loved ones still missing.

The blaze, which broke out at the factory around midday, was extinguished after three hours. But an adjacent chemical warehouse continued to burn, authorities said.

Large fires are relatively common in densely populated Bangladesh, often due to lax safety standards and poor infrastructure. Hundreds of people have been killed in fires in recent years.

As of Tuesday evening, the fire at the chemical warehouse in Mirpur had not been completely doused. Fire service officials have not determined which of the two buildings caught fire first.

According to eyewitnesses, the chemical warehouse stored bleaching powder, plastic, and hydrogen peroxide, all of which can intensify fires. Plastic also releases toxic fumes when burned.

Most of the deaths were caused by toxic gas and a locked roof door, the fire service stated. Victims likely died “instantly” after inhaling highly toxic gas, according to fire service director Mohammad Tajul Islam Chowdhury.

Police and military officers are still trying to locate the owners of the factory and the warehouse, with investigations ongoing into whether the warehouse was operating legally.

Tearful family members stood outside the charred buildings, many clutching photographs of their missing relatives. One father desperately searched for his daughter, Farzana Akhter.

Bangladesh has a long history of deadly industrial disasters.

In 2021, a fire at a food and drink factory killed at least 52 people, while the Rana Plaza building collapse in 2013 killed more than 1,100 individuals.