The 330-megawatt electricity supply has been suspended after a fire broke at the Shahjibazar power plant in Habiganj's Madhabpur upazila on Sunday morning.
Mijanur Rahman, chief engineer of the power plant, said they are working to restore the power supply but could not confirm when they will be able to do so.
According to the fire service headquarters control room, the blaze originated at around 9.45am and destroyed two transformers.
On information, five firefighting units from Moulvibazar and Osmaninagar rushed to the location but failed to douse the flame by using water cannon. Meanwhile, the fire department of RFL went there and helped bring the fire under control by blowing foam.
It took them three hours to douse the flame.
"The cause of the fire could not be known immediately," Engineer Mijanur Rahman said while speculating that an electric short circuit may have ignited the fire at the power facility.
According to unconfirmed sources, the fire broke out while burning grass and garbage near a transformer and within moments it spread to another transformer, STG hall and the control room nearby.
Engineer Mofiz Uddin Ahmed, manager of the old 100MW Shahjibazar power plant, has been assigned to investigate the incident. Prime Minister Sheikh Hasina inaugurated the new Shahjibazar power plant on 1 March 2017.