An investigation has been launched after a diver died while working on the wreck of the super yacht Bayesian.

The 39-year-old, who has not been named, was pronounced dead this afternoon, but it was not immediately clear if he was a local or a contractor with the recovery team.

A coastguard spokesman confirmed the incident but had no other immediate details to share following the incident which happened off the coast of Porticello near Palermo on the Italian island of Sicily.

Sources said the diver who died was Dutch and worked for SMIT, the operators of the heavy lifting crane that has been brought in along with another support ship to lift the yacht.

The investigation was focusing on two theories, that he either had a seizure of some kind or his oxygen equipment was faulty.

It was not immediately clear if the accident would impact on the lifting operation which is set to take place next weekend.

Marine salvage experts begAn a £20million operation to recover the wreck on May 5.

The vessel sank in a freak storm off the fishing village of Porticello, Sicily, last August, killing seven – including billionaire tech tycoon Mike Lynch, 59, and his daughter Hannah, 18.

The salvage mission, which will see the wreckage lifted 164ft from the seabed, is being carried out by two crane ships, Hebo Lift 2 and Hebo Lift 10.

Hebo Lift 2’s underwater technology will be combined with Hebo Lift 10, said to be one of the most powerful maritime structures in Europe, with the aim of raising Bayesian by mid-May.

Lifting the £30million, 543-ton vessel is key to an investigation launched by Italian authorities, who want to know why the yacht – which makers The Italian Sea Group claim was unsinkable – sank in just 16 minutes.

Pictured: the Italian Coast Guard’s Luigi Dattilo CP940 patrol vessel (right) assists Hebo Lift 2 (left) at the site

Lifting the £30million, 543-ton vessel (above) is key to an investigation launched by Italian authorities, who want to know why the yacht sank in just 16 minutes

Last August, Mr Lynch, the yacht’s owner and founder of Cambridge-based software firm Autonomy, invited a group of friends and family to the yacht to celebrate being cleared by a US jury of fraud charges that could have seen him jailed for 20 years.

In addition to Mr Lynch and his daughter Hannah, Morgan Stanley International Chairman Jonathan Bloomer and wife Judy, attorney Chris Morvillo and wife Neda, and ship’s cook Recaldo Thomas died in the shipwreck.

With the help of nearby vessels, 15 of the 22 total people on board were rescued in the initial phase – with one body recovered and six others reported missing.

The bodies of the six missing people were later found following search efforts which continued until August 23 last year.

In the days after the tragedy, the CEO of the Italian Sea Group lay the blame at crew members on the yacht.

Giovanni Costantino said: ‘This was human error, the yacht sank because it took on water.

‘From where exactly the investigators will tell us. The dynamic of the sinking is seen and read from AIS (Automatic Identification System) data and lasted sixteen minutes.

‘We have given this data to the prosecutors at Termini Immerse. From the images it looks as if the yacht had been taking on water for four minutes.

‘All it took was another gust of wind to turn her over, that meant more water coming in. She then straightened very briefly before going down.’

The vessel sank in a freak storm off the fishing village of Porticello, Sicily, last August, killing seven – including billionaire tech tycoon Mike Lynch (left) and his daughter Hannah (right)

Lifting the £30million, 543-ton vessel (above) is key to an investigation launched by Italian authorities, who want to know why the yacht sank in just 16 minutes

Mr Constantino told Italian newspaper Corriere della Sera there were a long list of errors; the stern hatch was ‘clearly’ open; the ship’s keel should have been lowered; people shouldn’t have been in their cabins’ and the crew should have known about the storm. 

He said the tragedy was avoidable and added: ‘Ask yourself – why were no fishermen from Porticello out that night? A fisherman reads the weather conditions and a ship doesn’t?

‘The storm was in all the weather charts. It couldn’t have been ignored.’

Nick Barke, head of salvage operations at Boats.co.uk, previously told MailOnline that the ‘only real way of knowing’ why the yacht sank would be to lift it to the surface.