British tech tycoon Mike Lynch died of asphyxiation after running out of oxygen, an inquest source said, citing initial tests carried out on Saturday after his body was recovered from the Bayesian yacht that sank off Sicily last month.

Lynch, his daughter Hannah, 18, the ship’s chef, and four other guests died when the British-flagged superyacht sank during severe and sudden weather off Porticello harbour, near Palermo, on 19 August.

Initial findings from an autopsy on Hanna’s body, which took place on Saturday, were inconclusive, the source told Reuters, ruling out only trauma as the cause of death and leaving open the possibility that she either ran out of oxygen or suffocated.

The bodies, with the exception of that of the chef, were found in cabins on the port side of the 56-meter ship.

The results of the autopsies on the remaining four victims –Jonathan Bloomer, chairman of Morgan Stanley International, his wife, Judith, and attorney Chris Morvillo and his wife, Nedda, all point to suffocation as a possible cause of death.

At the same time, it was confirmed that the cook, Recaldo Thomas, died of drowning

Fifteen people survived the tragic wreck, including Leeds’ wife and the yacht’s captain.