Prosecutors in Italy have placed under investigation the captain of a superyacht that sank during a storm off Sicily and claimed the lives of seven people, including Suffolk tech businessman Mike Lynch.

The captain was among 15 survivors of the sinking that killed Dr Lynch, his 18-year-old daughter Hannah and five others.

James Cutfield, a 51-year old New Zealand national, is being investigated for possible manslaughter and culpable shipwreck over the incident off Porticello last Monday, newspapers said.

READ MORE: Bodies of Mike Lynch and daughter found on Sicily yacht

Under Italian law, being under investigation does not imply being guilty and does not necessarily lead to criminal charges.

Prosecutors in Termini Imerese did not respond to calls to confirm the reports.

On Saturday, chief prosecutor Ambrogio Cartosio confirmed an investigation has been launched but said a suspect has not been identified.

He said his team will consider each possible element of responsibility, including those of the captain, the crew, individuals in charge of supervision, and the yacht’s manufacturer.

Mike Lynch was reported missing after the Bayesian sankMike Lynch was reported missing after the Bayesian sank (Image: Yui Mok)

The Bayesian, a 184ft (56m) British-flagged luxury yacht owned by Dr Lynch's wife, who survived, went down near the Mediterranean island in southern Italy last Monday.

Investigators are focusing on how a vessel deemed “unsinkable” by its manufacturer, Italian shipyard Perini Navi, sank while a nearby sailing boat remained largely unscathed.

READ MORE: Mike Lynch yacht: Two bodies found during search in Sicily

Prosecutors said the event was “extremely rapid” and could have been a “downburst” – a localised, powerful wind that descends from a thunderstorm and spreads out rapidly upon hitting the ground.

The crew were saved, apart from the chef, while six passengers were trapped in the hull.