Crucial data that might explain why the cruise ship the Costa Concordia ran aground off the coast of Italy is missing, an Italian newspaper says.
Documents leaked to the Corriere delle Sera have raised doubts over whether the black box data recorder was working at the time of the disaster in January.
The paper also says that watertight safety doors designed to prevent flooding, were left open.
More than 30 people died when the ship capsized near Giglio in January.
Italian investigators are holding an inquiry into the cause of the disaster.
The BBC’s Alan Johnston in Rome says information has been leaked to the media at every stage.
The latest claims suggest that as the black box was not working when the ship set sail, the investigation is having to rely on data gathered on less secure computing systems, which crashed two hours into the drama.
The ship’s owners. Costa Crociere, have said there was a report of a problem with the black box a few days before the ship sank, but that on the night of the disaster it was working perfectly.
The company also said the paper’s claims regarding the safety doors were not true.
A court hearing is due on July 21 at which the full results of technical analysis will be heard.
The ship was carrying 4,200 passengers and crew when its hull was torn open by rocks.
Captain Francesco Schettino faces charges of causing the incident by steering the Costa Concordia too close to the island’s shore. He denies the charges.