The fire broke out in the house of Ramdev Yadav and engulfed the surrounding residential area gutting all the 150 houses, Bachhwara police station's Station House Officer (SHO) Manoj Kumar Mahto said.
An unidentified 8-year-old girl was charred to death in the blaze, while two other children were feared missing, he said.
Several fire tenders were pressed into service to douse the flame, Mahto said.