Shahzaman breathed his last at United Hospital at 2:18pm, said Duty Manager of United Hospital Sabbir Ahmed.
He was admitted to the hospital on Tuesday, Ahmed said.
Shahzaman Mozumder was well-known for his contribution to the Liberation War in 1971.
He fought the battle of Ashuganj and the Muktibahini's march towards Dhaka in 1971.
He was the author of ‘The Guerrilla: A Personal Memorandum of 1971’.
Shahzaman Mozumder had also launched the country's first bespoke suit atelier - Dapper Bespoke.
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