Search teams have found eight more bodies in the wreck of the cruise ship Costa Concordia which capsized on 13 January.
The body of a girl of five is among those believed to have been found.
Officials say 32 people died in the disaster but only 17 bodies had been retrieved before the new announcement.
Prosecutors are investigating seven more people over the disaster including employees of the ship's operator, Costa Cruises, Italian media report.
The ship's captain, Francesco Schettino, has already been accused in Italy of manslaughter, causing a shipwreck and abandoning ship before all those aboard were evacuated. He denies wrongdoing.
His first officer, Ciro Ambrosio, is also under investigation.
The new suspects are said to be four of the Concordia's other officers and three employees of Costa Cruises.
Costa Cruises said it had "complete faith in the judicial system" and had offered its "fullest collaboration" with the Italian authorities.
Italian civil protection officials confirmed for BBC News that eight bodies in all had been found on Wednesday.
The discovery of four victims was announced initially.
All of the bodies are located near a part of the ship known as Bridge 4.
Officials said not all of the bodies had been recovered due to adverse weather conditions in the area.
One of the bodies found is said to be that of Dayana Arlotti, from Rimini, who had been on the ship with her father William, also missing.
Francesca Maffini told AFP news agency that an operation to recover the bodies was under way.
"The bodies are in a state of decomposition after all this time in the water," she said.
Pumping to remove more than 2,300 tonnes of fuel from the wreck began earlier this month.
Susy Albertini, mother of Dayana Arlotti, joined other relatives and friends of passengers to visit the scene of the wreck this month.
They threw roses into the water from a boat which took them within 50 metres (yards) of the Concordia, one month after the disaster.
William and Dayana had disappeared after returning to their cabin to get medicine for his severe diabetes, the Italian daily Corriere della Sera said.
The fact that seven more people had been placed under investigation was, Costa Cruises suggested, "simply due to the necessity for the authorities to provide such individuals with the guarantees afforded to everybody under Italian law" before a forthcoming hearing.
It said it had "complete trust and solidarity" in the seven people, "being absolutely confident in their professional competence and ethical correctness".
They had "performed their duties with the highest professionalism and dedication in the hours following [the disaster]", Costa Cruises added in a written statement.
The ship, carrying 4,200 passengers and crew, had its hull ripped open when it hit rocks in darkness, just hours into a Mediterranean cruise.
Some people were forced to swim for shore as the angle of the ship made launching lifeboats impossible.