The deceased were identified as Mahibul Islam Nipu, 40,and Rahmat Ullah , 35, and Abdul Khalek, 45.
According to local sources, the fire originated in an oil and LP gas shop owned by Mahibul at Chairmanghat Bazar around 9:30pm.
On information, three firefighting units rushed to the spot and extinguished the after two and half an hours of frantic efforts with the help of locals.
They recovered the charred bodies of Mahibul and Rahmat from the spot and rescued Khaled with severe injuries, said Mohammad Nur Nabi, sub-officer of Subarnachar upazila fire station.
Khaled was first admitted to Noakhali General Hospital from where he was taken to Dhaka Medical College and Hospital where he died around 6:30am on Tuesday, he said.
Besides, two firefighters were also injured in the fire incident.
At least 16 shops were gutted in the devastating fire.
Local administration and fire service formed two committees to investigate the incident.
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