As the Italian navy battled to complete the evacuation of the stricken ship, Bari prosecutor Giuseppe Volpe announced a probe to examine whether negligence contributed to the disaster in which at least one passenger died.
The investigation will seek to establish how the fire started and why it was able to gain such force that passengers feared they would be burned alive or suffocated by thick smoke.
The Italian owner of the boat has insisted that the vessel was in full working order and had passed a technical inspection which included its firedoors on December 19.
The Greek passenger who died yesterday was recovered from the water after apparently falling in while trying to reach a lifeboat.