Investigators examining the sinking of a luxury yacht off the coast of Sicily face a number of key questions.

In a press conference at Termini Imerese’s court on Saturday, Italian prosecutors announced a manslaughter and negligent shipwreck investigation over the deaths of seven people in the Bayesian superyacht disaster.

Officials were unable to answer a number of queries from the media, saying they needed time to establish the facts, and here the PA news agency identifies the key issues that the inquiry will look into.

– Why weren’t passengers who remained on board the vessel warned about escaping from the yacht?

The prosecutor in charge of the case, Raffaele Cammarano, suggested that some passengers may have been asleep when others were awake.

Asked why they were not woken up or alerted, he said that is something investigators are trying to work out from the statements of the survivors.

He called it an “essential” part of the inquiry, according to a translation.

– Why were several of the passengers in one cabin?

The press conference heard several bodies onboard the sunken yacht were found in a single cabin which was not theirs.

Mr Cammarano said investigators currently do not know the reason for them being discovered in the same cabin.

The chief of the Palermo fire service, Bentivoglio Fiandra, said the yacht pinned to the right and suggested people tried to go on the other side, taking refuge in cabins in the higher part of the wreck.

– Why did the boat sink?

The vessel had been deemed “unsinkable” by its manufacturer – Italian shipyard Perini Navi.

The Bayesian was hit by a downburst, according to Mr Cammarano, which are powerful winds that descend from a thunderstorm and spread out quickly once they hit the ground.

Officials will look into the safety equipment on the sunken vessel.

Mr Cammarano was asked about whether there is a black box and if the hatches were left open.

He said investigators do not have exact information about the black box and that the first phase of the inquiry will look into it.

– Why were nearby vessels not similarly affected?

Another yacht, the Sir Robert BP, was about 150 to 200 metres from the Bayesian when extreme weather hit.

Its crew helped to rescue 15 people from the stricken vessel.

Italian officials said they would be looking at how the downburst could affect one vehicle and not other nearby vessels.

– What weather warnings was the Bayesian alerted to?

Maritime director of western Sicily Rear Admiral Raffaele Macauda said the weather at the time of the yacht’s sinking was abnormal and there was nothing to suggest such an extreme situation would arise.

He said there were forecasts of winds and a storm alert, but there was no warning of a tornado.

According to a translation by the BBC, he said: “Given that the conditions were such, there wasn’t anything to suggest there could be an extreme situation arising.

“There are vessels that can monitor, after all, these events and one would have thought that the captain had taken precautions.”

– How long will it take to recover the sailing vessel?

Mr Macauda could not confirm how long it would take to retrieve the shipwreck of the sunken yacht.

“Everything depends on the availability of the owners and the timeframe of the retrieval of the wreck and of course all that has to be submitted to the port authorities and in parallel of course there will be the inquiry results and it’s only really then that we will be able to authorise the operation,” he said, according to a BBC translation.

“I can’t say, like some experts who have already spoken on the subject, that it will be eight weeks.”

He made clear that the owners will bear the full cost of retrieval, although he could not estimate the figure.