At least 78 people have died after fire tore through a heavily populated area of the Bangladesh capital, Dhaka.

Dozens more were injured in the deadly blaze and it is feared the death toll could climb higher as fire-fighters continue to search the wreckage for more victims.

The fire erupted in a four-storey warehouse in the Chawkbazar area of Old Dhaka on Wednesday night and quickly spread to four surrounding properties.

At least 50 people were taken to hospital, some in a critical condition.

The aftermath of a deadly fire in Dhaka, 21-02-2019. Image: Mohammad Al-Masum Molla/dpa

Mahfuz Riben, from Dhaka Fire Service and Civil Defence said: "Our teams are working there but many of the recovered bodies are beyond recognition. Our people are using body bags to send them to the hospital morgue. This is a very difficult situation."

Rescuers work at a fire site in Dhaka, Bangladesh, 21-02-2019. Image: Xinhua/Salim Reza

Samanta Lal Sen, head of a burn unit of the Dhaka Medical College Hospital said at least nine of the critically injured people were being treated in his unit.

Local reports suggest the building was full of highly flammable materials – with fire-fighters struggling to access adequate water supplies to fight the blaze.

Witnesses told local TV stations that many gas cylinders stored in the buildings exploded.

It is not yet clear what caused the fire.