A body believed to be that of Mike Lynch’s 18-year-old daughter has been recovered from the wreckage of a luxury yacht off the coast of Sicily, meaning all missing passengers have now been found.

The discovery comes as unconfirmed reports in the Italian media have said that prosecutors are set to announce a manslaughter investigation into the incident.

The Italian Coastguard said the sixth and final missing person had been located on the sunken Bayesian on Friday.

A green body bag was seen being brought to the port of Porticello from the site of the sinking.

Vincenzo Zagarola, of the Italian Coastguard, said the search for Hannah has not been “easy or quick”, comparing the sunken yacht to an “18-storey building full of water”.

Mr Lynch, his daughter Hannah, Morgan Stanley International bank chairman Jonathan Bloomer, his wife Judy Bloomer, Clifford Chance lawyer Chris Morvillo and his wife Neda Morvillo were lost when the yacht sank at around 5am local time on Monday.

Mr Zagarola said: “From the first moment, it has not been easy or quick to inspect the boat.

“Think of an 18-storey building full of water.”

The bodies of all six missing passengers have now been brought to shore in the small fishing village of Porticello, around 11 miles from the Sicilian capital of Palermo.

One of Hannah’s former teachers paid tribute to her after her body was recovered from the wreckage, saying: “I will remember her for what she taught me: kindness, compassion and commitment.”

Jon Mitropoulos-Monk, head of English at Latymer Upper School in Hammersmith, said: “I’ve never taught someone who combined sky-high intellectual ability with warmth and enthusiasm in the way Hannah did.”

Her friend Katya Lewis also paid tribute to Hannah, saying: “Being with Hannah made me feel whole and happy.

“She is the most special friend anyone could ask for and I will always love Hannah.”

Of the 22 passengers and crew on board, 15 – including Mr Lynch’s wife, Angela Bacares – were rescued after escaping on to a lifeboat.

The body of Canadian-Antiguan national Recaldo Thomas, who was working as a chef on the superyacht, was recovered at the scene of the sinking on Monday.

The boat trip was a celebration of Mr Lynch’s acquittal in a fraud case in the US.

The businessman, who founded software giant Autonomy in 1996, was cleared in June of carrying out a massive fraud relating to its 11 billion dollar (£8.64 billion) sale to US company Hewlett Packard.

Mr Zagarola previously said a decision on whether to raise the sunken yacht from the seabed is “not on the agenda”, but will be in the future.

The luxury yacht’s captain, James Cutfield, has reportedly been questioned by authorities in connection with the sunken yacht.

Giovanni Costantino, chief executive of the firm that built the yacht, told The Times it was “absurd” that passengers on the yacht were in their cabins.

He told the newspaper: “Why were (they) in their cabins?

“Local fishermen saw the storm was coming, why did no-one on board the Bayesian realise?

“From 3.50am, the captain had four minutes to get the passengers out of their cabins.”

He continued: “They should have jettisoned the anchor, started the engine, pointed the bows to the wind and put the keel down.

“If they had done that, no-one on board would have been afraid, they would have been back to bed in an hour and ready to push on with their voyage.”

Tributes have been paid to those who died in the disaster, with some describing Mr Lynch as a “visionary unlike any other”.

Eleanor Lightbody, the chief executive of the legal AI company he founded called Luminance, said: “He had a unique ability to spot the next technological revolution and solve tomorrow’s challenges before others even knew they were coming.

“Above all, Mike was a kind man who had an impact on many and will be sorely missed. I feel honoured to have known him, worked with him and learnt from him over the years.”

In a statement confirming their parents’ deaths, the Bloomer family described the couple as “incredible people and an inspiration to many”.

They said: “Our parents were incredible people and an inspiration to many, but first and foremost they were focused on and loved their family and spending time with their new grandchildren.

“Together for five decades, our only comfort is that they are still together now.”

A helicopter, remotely controlled underwater vehicles, naval units and cave divers have been used in the search.

Bayesian was moored around half a mile off the coast of Porticello when it sank as the area was hit by a storm.

The wreckage of the Bayesian is resting on the seabed off the coast at a depth of 50 metres (164ft).

Prosecutors in the nearby town Termini Imerese are scheduled to hold a press conference on Saturday morning.