The officials failed to specify time of resuming electricity connection.
Deputy Commissioner M Kazi Emdadul Islam said the fire was extinguished but the power was gone in the whole district.
“But, it is not clear when the power connection will return to normal.”, he said.
The local administration announced about the prolong power cut across the district to minimize the public hazards, Islam said.
A specialized body will be formed to investigate the cause of the fire and measure damages caused by it, he added.
Meanwhile, a member of Firefighters Jayanta Kumar got injured trying to douse the flame and was admitted to Sylhet Osmani Medical College Hospital.
Earlier, Mokammel Hossain, chief engineer of Sylhet Polli Bidyut Distribution Department, said the fire broke out at the Kumargaon 120MW Power Station around 11:30am.
Four firefighting units rushed in and contained the fire at 12:15 pm.
The cause of the fire could not be known immediately.
Power supply to Sylhet district remained suspended since the incident.
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