This article is more than 2 years old

This article is more than 2 years old

Greek police are conducting an investigation into the death of an Australian model onboard a superyacht off the Ionian island of Kefalonia.

Three days after the body of Sinead McNamara was discovered at the back of the luxury vessel, local police said they had broadened an inquiry into her death.

“The yacht left our waters last night but we are still gathering evidence,” Kefalonia’s police port official, Stamatis Limneos, told the Guardian. “The inquiry is ongoing.”

Local media reported that the 20-year-old had killed herself, with news outlets saying she was found in a comatose state in a cabin.

The model, originally from Port Macquarie, had been employed as a crew member on the 93.25-metre Mayan Queen IV, owned by the Mexican mining magnate Alberto Baillères.

The billionaire businessman is believed to have left the yacht last Tuesday and only crew members were onboard at the time of McNamara’s death. A father of seven, Baillères is listed as the world’s 143rd wealthiest individual with a net worth of $9.6bn (£8.26bn), according to Forbes magazine.

The news site Kefalonia Press reported that doctors had desperately attempted to revive the model who was rushed to a hospital on the island. An autopsy was due to be conducted in Athens.

Authorities were believed to be focusing on the six-storey ship’s closed-circuit camera. Police had spent the past three days questioning staff, another official said.

The model, who had more than 14,000 Instagram followers, had posted a cryptic message on the site two weeks ago. “Take me back to where my only worry was not cracking my skull open,” she wrote under an image showing her on a Greek quad bike before a panorama of hills.

Australia’s Department of Foreign Affairs and Trade said it was providing consular assistance to her family.

Devastated friends posted tributes to her on social media over the weekend. “I lost a girl who opened my mind to the world,” one friend from Port Macquarie wrote on Facebook.

McNamara had been working on the £108m motor yacht for the past four months.

She joins a growing list of young employees, enticed by the perceived glamour of working for the rich on the high seas, to have met untimely ends on luxury vessels owned and chartered by billionaires. At least three young Britons have lost their lives on superyachts, in which spas, cinema rooms and multi-level swimming pools are considered de rigeur, in recent years.

In a sector that employs more than 37,000 people, the number, globally, is thought to be much bigger.

The construction of superyachts has soared with the emergence of ever more billionaires on the back of booming stock markets following the election of the US president, Donald Trump. Superyacht sales across Asia have surged, industry figures say.

The luxury boat business in the UK has recorded record sales following the fall in the pound post-Brexit, with exports mainly to the US, the largest boat market in the world.