One of the non-AC coaches of the train had caught fire at Kayamkulam near Alappuzha after Nivaz, hailing from Vellore in Tamil Nadu, tried to commit suicide by setting himself on fire in its toilet on August 16.
"He was brought to this hospital with 60 per cent burn injuries on August 16. He died at 2.20 PM today while undergoing treatment," a spokesperson for the Ernakulam Medical Center said.
Passengers of the train, originated from Thiruvananthapuram, had a narrow escape in the incident as the train was about to depart from Kayamkulam around noon.
He was rushed to Alappuzha Medical College Hospital soon after the incident.
Later, he was shifted to the private hospital here by police for providing him better treatment.
Police suspect the man was mentally unstable.