Morgan Stanley International chairman Jonathan Bloomer is among those missing, along with UK tech entrepreneur Mike Lynch, as Italian authorities continue to search the wreckage of the luxury yacht that sank during a storm off the coast of Sicily.
Specialist divers from Palermo's fire and rescue service told local media that search operations resumed Tuesday morning. Firefighters said gaining access to the yacht, which is 48 meters (157.5 feet) below the surface, was "complex".
The head of the civil protection agency in Sicily, Salvo Cocina, said in a message to Bloomberg that the six passengers still missing are Bloomer and his wife Judy, Clifford Chance partner Chris Morvillo and his wife Nada, as well as Lynch and his daughter Hannah.
Of the 12 guests and 10 crew who were on the yacht named Bayesian, at least one person has died. Lynch and his family were aboard with a small group of his financial and legal advisers celebrating the tycoon's recent acquittal from fraud charges when the violent storm hit.
Prosecutors in Sicily opened a probe into the sinking of the yacht and have spoken at length to a skipper who was on board, Italian media reported on Tuesday. They believe the most likely explanation is that the Bayesian's mast snapped during an extraordinary bout of bad weather.
The UK's Marine Accident Investigation Branch has also sent a team of inspectors to the area.
The Bayesian, which at 56 meters (184 feet) long was one of the world's largest sailing yachts, had been anchored in waters hit by a marine spout, a column of air and water mist that can cause intense damage.