At least 16 people were killed Tuesday when a fire tore through a chemical and garments factory in Bangladesh's capital Dhaka, officials said.

The blaze began in the factory's warehouse before spreading to a nearby multi-storey garments facility, said Tajul Islam Chowdhury, director at the Fire Service Department.

All the bodies were recovered from the garments factory, Chowdhury told reporters, confirming the toll.

Outside the factory, distraught relatives searched for loved ones. Abdur Rahman, 19, said he was looking for his brother Robin.

"I found one of his colleagues, who escaped by breaking a window. He saw my brother Robin inside," Rahman told AFP. "He didn't make it."

Several others held up pictures of missing loved ones, pleading for information.

"The deceased appeared to have suffered severe inhalation injuries from the chemicals, as there were highly flammable materials stacked inside," Chowdhury told reporters.

Authorities have yet to enter the chemical warehouse.

Tahmina Sharmin, 34, a witness, said she heard a loud explosion before the area was filled with flames and smoke.

"People were startled and didn't know what to do at first," she told AFP.

She said she was among the first to respond before fire crews arrived.

More than 26,500 fires were reported last year alone in Bangladesh, where safety standards are lax and often ignored.

In 2021, at least 52 people were killed including many children when a fire swept through a food processing factory.

Bangladesh's worst fire took place in 2012, when a blaze ripped through a garment factory on Dhaka's outskirts, killing at least 111 people and injuring more than 200 others.