He said the explosion took place on the ground floor of a seven-storey building on Syed Nazrul Islam Avenue in Gulistan. A rescue operation is underway on the first and the second floors of the building.

"We have recovered four bodies so far and more people are likely to be injured in the explosion,” Dinomoni Sharma added.

Earlier, the fire service in an SMS said they received the news of an explosion beside the BRTC bus counter around 4:50pm.

Five units of fire serve rushed to the stop and began the rescue operation. Two more units joined the rescue operation later.

On Saturday, seven people were killed and score others injured after explosions occurred at an oxygen factory in Sitakunda, Chattogram.

The next day, three people were killed in an explosion at a building at the capital’s Science Laboratory area.

The fire service, however, could not confirm the cause of the today's explosion.

“We are busy with rescue operation now,” Dinomoni Sharma said.