One man has been found dead and six other people are missing – presumed dead – after a luxury yacht capsized whilst anchored close to Porticello harbour, on the Italian island of Sicily.

The 56m (183ft) long Bayesian was less than half a mile off-shore, near to the capital Palermo, when it was suddenly hit by a violent storm that threw up a “tornadic water spout”, at around 5am local time on 19 August, with reports suggesting the vessel immediately tipped over.

The yacht, which was flying a British flag, had 22 people on board, which consisted of 10 crew and 12 passengers, made up of mainly Brits, but also American, Canadian, New Zealand, French, Irish and Sri Lankan nationals.

Emergency services were on the scene quickly and with the help of nearby boats were able to rescue 15 people, including a one-year-old child.

One of those missing has been reported to be Mike Lynch, a 59-year-old British technology entrepreneurial tycoon, who was the co-founder of the Autonomy Corporation and founder of Invoke Capital.  

The gender or nationality of the person who was found dead has not yet been confirmed.

Only 700m from shore

The Bayesian left the Sicilian port of Milazzo on 14 August and was last tracked east of Palermo on the evening of Sunday 18 August, with a navigation status of “at anchor”.

It was only around 700m (2,296ft) from Porticello harbour, which was nothing unusual for larger vessels as they are often too big for the relatively small harbour.

The Italian Coast Guard reported the sinking of the vessel and added in a statement: “The first shipwrecked were rescued by a boat in the immediate vicinity and brought ashore by four Coast Guard vessels, which promptly responded to the scene.”

Waterspout created by storm

CCTV footage shows how torrential wind and rain hit Santa Nicolicchia, which is the area of Porticello where the yacht was anchored. A waterspout has been reported by witnesses as developing within the storm.

Waterspouts can form over water during bad weather, and are essentially funnel-shaped columns of rotating, cloud-filled wind and are highly dangerous and can be destructive. Often referred to as “tornadic waterspouts”, they are usually an accompaniment of severe thunderstorms and lightning strikes.

They have been known to overturn boats and damage large ships in the past and this appears to have been the case here.

Six still missing

Four British passengers, two Americans and a Canadian are said to be missing, although which of those is the one recovered body has not yet be confirmed.

Of the other 15 on board, eight had been taken to hospital, but early reports suggest most are stable and none are thought to be in life-threatening conditions.

Mother’s desperate fight to save one-year-old daughter

The one-year-old English girl, named in local press as Sophie, was taken to the children’s hospital with her mother, named by local reporters as Charlotte, who told how she had held her daughter “with all my strength, my arms stretched upwards to keep her from drowning.”

She said she had battled desperately to keep her eyes open in the pitch black darkness and had “screamed for help” but said all she could hear around her was the “screams of others”.

Doctor confirms good prognosis

Dr Domenico Cipolla, head of emergency room at the Giovanni di Cristina paediatric hospital in Palermo, confirmed that both were in good condition “all things considered”.

He said: “All the doctors and nurses were all very moved, because the little girl is fine, the prognosis is good and we are carrying out tests just to be careful.”

Bodies spotted through portholes by divers

The person who died was found by a helicopter scouring the area, with photos showing emergency services carrying a body bag from the water.

It later emerged that the yacht had been located around 50m below the surface and Salvo Cocina, the head of the Civil Protection of Sicily, reported that divers had seen “corpses through the portholes” of the vessel.

Entrepreneur feared drowned

One of the missing is being reported to be Mike Lynch, the British tech entrepreneur, who founded the software company Autonomy in 1996 and became one of Britain’s most high-profile businessmen when he sold it to Hewlett Packard for £7bn in 2011.

Mr Lynch’s wife, Angela Bacares, is among those rescued.

Trawler captain quick to the rescue

Karsten Borner, the captain of a nearby trawler, was hailed a hero after rescuing 15 people from a life-raft. He described the conditions in which the Bayesian sank, saying his own vessel was battered by very strong gusts in the early hours of the morning, but had managed to stabilise it by using its engine.

He spoke of noticing the Bayesian nearby and actually manoeuvred to avoid hitting it. “We managed to keep the ship in position, and after the storm was over, we noticed that the ship behind us was gone.”

One of largest super-yachts

The super-yacht is managed by Camper and Nicholson’s International and had previously been described as one of the largest of its type in the world.

It was built in 2008 by Italian yacht builder Perini Navi. And had an initial asking price of 35 million euros (£30 million).

The luxury vessel had six suites, and was given the accolade of the “best exterior styling” at the 2009 World Super-yacht awards.Renting the yacht set customers back £166,000 per week.

Parts of Mediterranean experiencing unseasonally bad weather

The western half of the Mediterranean has seen frequent, severe storms over the past week, with low pressure dominating.

Flights have been cancelled and beaches closed across some of the most popular holiday hotspots in France and Spain, with a warning also issued for parts of Greece.