Authorities in Italy have opened a manslaughter investigation into the sinking of a superyacht, which killed seven people off the coast of Sicily earlier this week.

Announcing the probe, prosecutor Ambrogio Cartosio said investigators found it was not the weather that caused the ship to sink, but was a result of the behavior of the crew and the way the boat was handled.

He said the investigation was not aimed at any individual.

“There are many possibilities for culpability.  It could be just the captain. It could be the whole crew. It could be the guard. We are evaluating all of the factors to see whose behavior fault can be assigned to,” Cartosio said.

He added that the prosecutor’s office had “filed a dossier, at present against unknown persons, alleging the crime of negligent shipwreck and manslaughter.”

While the reasons for the sinking of the Bayesian superyacht remain unconfirmed, many believe the yacht was struck by a waterspout — one of several types of tornadoes. The coast guard reported the yacht was struck by a tornado, and a waterspout was reported to the European Severe Weather Database around the same time.

This is a developing story and will be updated.

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