One of the men, who suffered severe burns in an explosion in Chattogram's Double Mooring area, succumbed to his injuries on Sunday night.
The deceased was identified as Shah Alam, 38, son of Adam Ali Khan of the area. He had suffered 100 percent burns.
Sadip Kumar Das, officer-in-charge of Double Mooring Police Station, said the explosion took place on Saturday night when Shah Alam was working on the water tank of the house of one Belal Khan. Four people -- Alam, Md Babul, 35, Sabuj Mia, 17, Najrul Alam, 60 -- were injured in the blast.
They were taken to Chattogram Medical College Hospital.
Of the injured, Alam, Babul and Sabuj were shifted to Sheikh Hasina National Institute of Burn and Plastic Surgery where Alam died on Sunday night. Sources say the other three have suffered 85 percent burns.
Police said it is unclear what sparked the explosion but suspect that an electric short-circuit or accumulated gas inside the tank might have caused the blast.
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