Alam, 35, Ramzan, 22 and Rifat, 12, are in critical condition with bronchial burn injuries. Alam had 72 percent burns on his body, Ramzan 58 percent, and Rifat had 28 percent burns.
According to the police, all three burn victims are house painters by profession and residents of Cumilla. They live in a rented tin-shed house in West Deobhog Bashmuli area where the explosion took place.
Fatullah Model Police Station Officer-in-Charge (OC) Nure Azam said police visited the spot after receiving the news of the explosion.
He suspected that the explosion might have been caused by a faulty gas line riser inside the tin-shed house, he said.
Police are investigating the matter, the OC added.