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Search for two remaining bodies to resume on Thursday

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Four bodies retrieved from sunken superyacht

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Victims not yet named by Italian authorities

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Prosecutors investigating the cause of the sinking

PORTICELLO, Italy, Aug 22 (Reuters) - Search efforts off

the coast of Sicily for two remaining bodies missing from the

sunken yacht belonging to the wife of British tech magnate Mike

Lynch were due to resume early on Thursday.

On Wednesday four bodies were retrieved from the wreck and

transported to nearby hospitals, in the city of Palermo.

A source said a fifth body might have been located late on

Wednesday, but the fire brigade and the coast guard, overseeing

the operations, did not confirm this.

Italian authorities did not officially identify the corpses,

but Britain's Daily Telegraph reported that two of the dead were

Lynch and his 18-year-old daughter. Italy's Corriere della Sera

said the only bodies identified so far were Morgan Stanley ( MS )

banker Jonathan Bloomer and U.S. lawyer Chris Morvillo.

The British-flagged Bayesian, a 56-metre-long (184-ft)

superyacht carrying 22 passengers and crew, was anchored off the

port of Porticello, near Palermo, when it disappeared beneath

the waves in a matter of minutes after a fierce storm struck.

Fifteen people, including Lynch's wife, managed to escape

the boat before it capsized, while the body of the onboard chef,

Canadian-Antiguan national Recaldo Thomas, was found near the

wreck hours after the disaster.

Operations have been challenging due to the depth and the

narrowness of the places that the divers are scouring, the fire

brigade said in a statement.

It compared the efforts to those carried out, on a larger

scale, for the Costa Concordia, the luxury cruise liner that

capsized off the Italian island of Giglio in January 2012,

killing 32 people.

UNSINKABLE

The disaster has baffled naval marine experts who said such

a vessel, built by Italian high-end yacht manufacturer Perini

and presumed to have top-class fittings and safety features,

should have been able to withstand such weather.

Prosecutors in the nearby town of Termini Imerese have

opened an investigation and authorities have started questioning

passengers and witnesses.

The captain and crew have made no official comment on the

disaster.

Giovanni Constantino, CEO of the Italian Sea Group

, which includes Perini, said the Bayesian was "one of

the safest boats in the world" and basically unsinkable.

He added that he believed the disaster was caused by a chain

of human mistakes and that the storm had been expected, in

interviews with Italian media.

"The ship sank because it took on water, from where

investigators will have to say," Costantino told television news

programme TG1 late on Wednesday.

Citing data from the yacht's automatic tracking and based on

available footage, Costantino said it took 16 minutes from when

the wind began buffeting the yacht and it began taking on water

for it to sink.

Costantino said the Milan-listed group had suffered

"enormous damage" to its reputation, with shares falling 2.5%

since the disaster.