Two more bodies have been recovered from the wreck of the Costa Concordia cruise ship on the Tuscan island of Giglio, rescuers said, bringing the official death toll to 15.
"Two more bodies, two women, were found near the Internet cafe," Franco Gabrielli, who is overseeing operations on Giglio, said.
Emergency workers in Italy say there may have been unregistered passengers on board the cruise liner.
Officials admit that they are unsure about the exact number of people still missing as a result.
Meanwhile, the operators of the Costa Concordia faced questions over their share of the blame for the shipwreck.
Captain Francesco Schettino is accused of steering the 290 metre-long cruise ship too close to shore while performing a manoeuvre known as a "salute" in which liners draw up very close to land to make a display.
Mr Schettino, who is charged with multiple manslaughter and with abandoning ship before the evacuation of 4,200 passengers and crew was complete, has told prosecutors he had been instructed to perform the manoeuvre by operator Costa Cruises.
Prosecutors say he steered the massive ship within 150 metres of Giglio, where it struck a rock that tore a large gash in its hull, letting water flood in and causing the 114,500-tonne ship to capsize.
Blaming the captain for the incident, Costa Cruises said the shipwreck was an "unfortunate human error". It has suspended Mr Schettino and will not be paying his legal fees.
Costa Chief Executive Pier Luigi Foschi has said that ships sometimes engage in "tourist navigation" in which they approach the coast but that this is only done under safe conditions and he was not aware of any riskier approaches so close to the shore.
