The chairman of Morgan Stanley International, Jonathan Bloomer, and his wife are among those missing after a yacht sank off the coast of Sicily, the UK insurer Hiscox said Tuesday.

"We are deeply shocked and saddened by this tragic event," Aki Hussain, Group CEO of Hiscox, which Bloomer has also chaired since 2023, said in a statement.

"Our thoughts are with all those affected, in particular our Chair, Jonathan Bloomer, and his wife Judy, who are among the missing, and with their family as they await further news from this terrible situation."

Six people, including UK tech tycoon Mike Lynch and his teenage daughter, are missing following the yacht capsizing early Monday.

The British-flagged Bayesian, which had 22 people aboard including 10 crew, was anchored some 700 metres from port before dawn Monday when it was struck by a waterspout, a sort of mini tornado.

Bloomer, 70, has led a number of financial services organisations during his decades-spanning career. 

He was a partner at Arthur Andersen before joining British firm Prudential plc in 1995, initially as its chief financial officer and then taking the role of CEO from 2000 to 2005. 

He was then an operating partner at Cerberus Capital Management, the United States private equity and alternative investor, between 2006 and 2012.

Described as a seasoned board director, occupying various roles, Bloomer had been chair of Morgan Stanley International since 2016, according to his LinkedIn profile.