The injured were identified as Aslam, Rabiul, Akash and Helena, all are jute mill workers.
Officer-in-Charge of Digholia Police Station Ahsanullah Chowdhury said one injured was sent to Dhaka in severe condition.
In-Charge of Digholia Fire Service Masud Parvez said the fire occurred at Hard West Machine of the mill in the noon and spread rapidly.
Four units of firefighters douse the flame after one and half hours of frantic efforts, he said.
Deputy General Manager of the mill Md Ripon Molla said they have lost jute and machines worth around Tk 50 lakh.
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