Divers resumed the search for survivors today after British businessman Mike Lynch’s yacht sank off the coast of Sicily in a fierce storm two days ago, although hopes of finding any of the six missing alive are fading.

The British-flagged Bayesian, a 56m sailing vessel, was carrying 22 passengers and crew and was moored just outside Porticello harbor when it capsized during a heavy storm before dawn yesterday, Monday.

Fifteen people survived, the body of one man who died was quickly recovered, and six people remain missing, including Lynch, his 18-year-old daughter and Jonathan Bloomer, non-executive chairman of Morgan Stanley International.

A Reuters photographer saw coastguard vessels leaving Porrichello this morning heading for the crash site after the search was called off overnight.

According to the Italian news agency ANSA, late yesterday, Tuesday, fire service divers managed to remove a three-meter-wide window from its hinges and used the opening as an entry point. They were able to reach the common area of ​​the boat, but not the cabins, the Italian fire service said. Rescuers said this will take some time as some entrances may be blocked. Efforts continue, although the vessel is lying on the seabed on its starboard side, a position that makes operations more difficult.

With the sunken vessel lying at a depth of about 50 meters, efforts to locate survivors or bodies are becoming difficult.

Fire officials say divers only have 8-10 minutes at the wreck site before resurfacing. Their efforts are being hampered by the “very tight spaces” inside the sunken vessel, fire service spokesman Luca Cari said.

Experts are struggling to explain how a large luxury vessel, which reportedly had the highest level of equipment and safety features, could have sunk within minutes, according to eyewitnesses. Another yacht, which was anchored next to it, was not harmed by the storm.

Matthew Shank, president of the Maritime Search and Rescue Board, said the Bayesian was the victim of a very intense and rare weather event.

“Looking at extreme weather conditions, if it was a water vortex, as it appears to have been, I would categorize it as a “black swan event” — an event that is very difficult to predict under normal circumstances, but in retrospect seems to have been inevitable), he told Reuters.

He said he was confident authorities would go “to the bottom” of what caused the wreck, thanks to descriptions from survivors, witnesses and an examination of the ship, which appears to remain intact on the seabed.