The fire at Gokul Niwas building in Kalbadevi on April 9 had claimed the lives of assistant divisional fire officer S W Rane and station officer M N Desai the same day.
Amin was battling for life for the last six days, and had undergone a few surgeries. "We tried our best, but could not save him," said a doctor at the National Burns Centre, Airoli.
"We operated on his lower limbs and wanted to perform further operations, but his kidney was not functioning well and he was on ventilator for the last three days," said a hospital official, adding that Amin showed a remarkable willpower to survive.
Maharashtra Governor Ch Vidyasagar Rao expressed grief over Amin's death.
"Shri Amin demonstrated exemplary courage while discharging his duty... . He risked his own life to save that of others. Shri Amin is a martyr who died in the line of duty," the Governor said in a message.
Chief Minister Devendra Fadnvis also condoled Amin's death.