The body of billionaire tech mogul Mike Lynch was recovered off the coast of Sicily, the Italian Coast Guard announced on Thursday. Lynch’s 184-foot superyacht, the Bayesian, sunk on August 19th, reportedly after being hit by a tornado over the water, called a waterspout. The yacht sank quickly, according to reports, even though its manufacturer claimed it was unsinkable.

Lynch was on the yacht with family and friends celebrating his acquittal on fraud charges in June. HP, which bought Lynch’s company, Autonomy, for $11 billion in 2011, had alleged “accounting improprieties” that misrepresented Autonomy’s value. In an interview with the BBC — the only broadcast interview before the yacht sank — Lynch said his wealth helped him deal with the decade-long legal battle.

The yacht was hit by a waterspout around 4AM local time, according to news reports. Fifteen people — including a baby — managed to escape on a life raft and were rescued by the crew of the Sir Robert Baden Powell, a Dutch ship that was anchored nearby. “They were all under shock,” Karsten Börner, the captain of the Sir Robert, told The New York Times.

Five other bodies were recovered, including that of Christopher Morvillo, one of the attorneys who defended Lynch in the HP trial. Lynch’s 18-year-old daughter, Hannah, is still unaccounted for.

Investigators are looking into why the Bayesian sank when other boats, including a nearby sailboat, were largely unaffected, The Associated Press reports. Börner, the Sir Robert’s captain, told AP that his ship also sustained minimal damage. 

Giovanni Costantino, the CEO of the Italian Sea Group — the company that owns the Bayesian’s manufacturer — described Lynch’s yacht as “one of the safest boats in the world” and said the accident likely occurred because the crew didn’t follow basic safety procedures.