A fire at the early hours gutted 20 tin-shed houses at the Sweepers' Colony in Kaptan Bazar near Jai Kali Temple.
Four people sustained burn injuries and were admitted to Sheikh Hasina National Institute of Burn and Plastic Surgery. They are Gita Rani, 64, Kanta Rani, 60, Raju, 60, and Afzal Hossain, 52.
The blaze broke out at the colony around 3:20am on Monday and spread soon.
Fire Service's director Lt Col Tajul Islam Chowdhury said a total of seven firefighting units managed to douse the fire at about 4:30am.
"Primarily it is suspected that the fire might have originated from a gas cylinder explosion. Other residents, whose houses under Hanif flyover, have been removed," he added.
It was learnt that there are total of 42 houses in two sheds for the sweepers under the Hanif flyover. Of those, 20 were burnt down.
Fire burns down 20 houses at Kaptanbazar, 4 admitted to burnt unit
