Dewan Azad Hossain, duty officer of Dhaka fire service and civil defence control room, said the fire broke out on the first floor of the building following the cylinder blast around 4.30am, leaving all the four members of the family injured.

A fire service team rushed to the spot and extinguished the blaze.

The injured were immediately taken to Munshiganj General Hospital from where they were shifted to Dhaka Medical College and Hospital, he added.