Sicily witnessed a tragedy on Monday, August 19, when the luxury yacht Bayesian sank due to a waterspout, resulting in what has been described as “an unbelievable story.” The yacht, carrying 22 passengers, saw most rescued, but six were confirmed dead, including British technology entrepreneur Mike Lynch. The last person still missing is Lynch’s  18-year-old daughter, Hannah.

This incident raised concerns from Giovanni Costantino, leader of The Italian Sea Group. According to CNN, Costantino questioned how those on board failed to notice the brewing storm and the issues with the supposedly “unsinkable ship.” He stated, “Everything that happened reveals a series of significant errors. The passengers should not have been in the cabins, and the boat should not have been at anchor. Why didn’t the crew know about the incoming disturbance?”

Costantino further noted that weather charts had already signaled the natural disaster, making it hard to understand how the passengers were caught off guard. “The passengers reported that the storm came unexpectedly, but that’s not true. Everything was predictable. I have the weather charts in front of me. Nothing came suddenly,” he said. He also pointed out that the absence of fishermen in the area should have been a clear warning sign.

A fisherman, Pietro Asciutto, who witnessed the sinking, shared his perspective according to the Washington Post . “I was at home when the tornado hit. I immediately closed all the windows,” he said. He continued, “Then I saw the boat— it had only one mast, and it was very large. I saw it sink suddenly… The boat was still floating, and then, suddenly, it disappeared.”

This tragedy follows the revelation that the late Mike Lynch, who owned Bayesian , had listed the yacht for sale in March for £30 million (approximately $39 million USD), according to the Telegraph. He later reconsidered and removed it from the market to set sail in the summer, with plans to relist it in the fall.

According to PEOPLE, the passengers on board were celebrating Lynch’s recent acquittal in a financial fraud trial in the U.S. An insider shared, “That’s why he took his closest friends and colleagues on the trip.”