The investigators determined that the tragedy had been caused by a neglected refrigerator truck, whose engine had not been turned off and had been exacerbated by a host of allegedly negligent acts, such as unfit fire equipment and a malfunctioning fire alarm.
Among the indicted are Carlo Visentini, of the Visemar company that owned the ferry, captain Argilio Giacomazzi, and 26 crew members.
On 28 December 2014, a fire broke out on the ferry that was travelling from Greece to Italy, killing 31 people and injuring another 64.
Anek Lines, the company operating the ship, said 478 people were aboard when the fire broke out. The majority of passengers were Greek citizens. Following the outbreak of the fire, Greek and Italian authorities launched a joint rescue operation, promising to assist everyone who was on the burning ship.
The ferry caught fire at about 6 a.m. local time (4:00 GMT), when the vessel was 33 nautical miles away from the Greek island Othonoi.