Three labourers and a boy sustained burn injuries as the boiler of a rice husking mill exploded in Kalai upazila of Joypurhat yesterday.
The injured are Abdul Latif, 45, and his wife Salma Begum, 38, and Osma Begum, 36, and her three-year-old son Sagar of Sitahar village in the upazila.
They were admitted to Shaheed Ziaur Rahman Medical College Hospital in Bogura.
Abdul Latif Khan, officer-in-charge of Kalai Police Station, said when the three labourers were heating the boiler of the mill of Shamim Hossain at Duranj village, it exploded suddenly with a big bang. The boy was present there with her mother at the time.
Later, locals rescued the four and sent them to the upazila health complex, said the OC.
They were later shifted to Shaheed Ziaur Rahman Medical College Hospital, said the police official.