As the search for the missing continues, questions remain about what exactly led a large luxury yacht to seemingly sink in minutes off the coast of Sicily — and investigators are still looking for answers more than 48 hours later.
There were 22 people on board when the Bayesian, a 183-foot vessel, sank around 5 a.m. local time on Monday while moored about a half mile from the coast of Porticello, the Italian coast guard said in a statement that was previously obtained by PEOPLE.
In the aftermath of the tragedy, 15 people were rescued, according to the cost guard. Six people were declared missing after the yacht sank — and five bodies have since been found in the wreckage — while a body was also separately retrieved near the vessel and later identified as chef Recaldo Thomas.
One theory is that the boat capsized after being struck by a waterspout (which refers to a tornado over the water), though there may have been more factors at play that contributed to the sinking.
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“The dynamics aren’t clear — lightning, mini tornado, water spout, it’s not clear exactly what happened,” one person close to the search efforts tells PEOPLE. “The most likely hypothesis is that the cause was indeed a tornado that began at land and then sped out off coast and became a waterspout at sea with a speed of more than [180 miles] per hour, to the point that it managed to practically sink the ship whilst causing minimum damage to both the mast and the hull.”
“Eyewitnesses said the boat went down in minutes,” this person adds.
The source says the vessel’s upper hatches could have been open at the time of the disaster, which would have caused the boat to quickly fill up with water. The source also says that large amounts of water may have flowed onto the ship through the hatches as the vessel rocked back and forth during the storm.
“This would be the only thing that could cause the hull to rear up which, as several survivors told the investigators, made the ship sink in literally 60 seconds,” the source says.
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The boat’s 236-foot mast may also have also played a role in allowing the boat to rock, similar to a pendulum.
Speaking with the BBC, Matthew Schanck, chair of the Maritime Search and Rescue Council, said that the large mast may have acted more like a sail during the strong winds.
As for whether it broke, Karsten Borner, a captain on a nearby boat who saw what happened and helped rescue survivors, told an Italian newspaper that he did see the mast “bend and then snap,” according to the BBC.
“The evidence that we are getting from the divers is the vessel is basically intact, lying on its side reportedly,” Schanck, the chair of the outside search and rescue council, said while speaking with the BBC. “If the mast was broken, that would be a significant thing that would be reported.”
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Another factor that could have caused the yacht to lose stability was its movable keel, which is an underwater blade designed to help keep boats upright and prevent them from swaying back and forth, the source close to the investigation tells PEOPLE.
They say that the 30-foot keel was allegedly retracted to about 13 feet when the storm hit, while natural experts say it would have been strange to retract the keel at that location if the crew knew bad weather was approaching.
Speaking with USA Today, meteorologist Rick Shema said that while the waterspout “was an uncommon occurrence” that “these things happen, especially in warmer water.”
Schema went on to note that on the day the ship sank, the water was about 3 degrees hotter than on average, which can likely be attributed to climate change.
One person still remains missing as crews continue to investigate the fatal incident, a source close to the investigation previously told PEOPLE.
The six people who disappeared after the storm are British entrepreneur Mike Lynch and his daughter Hannah, New York City-based lawyer Christopher Morvillo and his wife, Neda, as well as Morgan Stanley International chairman Jonathan Bloomer and his wife, Judy.
Authorities have not confirmed the identities of the five victims already removed from the wreckage.
Search efforts are ongoing, officials say, including inspection of the wreck.
