Australian Model Sinead McNamara Called Family Crying Before Death

Her family's lawyer is asking authorities to investigate the circumstances around her death.

An Australian model who died on board a superyacht in Greece had called a family member crying about an incident involving another crew member, according to the family's lawyer.

Sinead McNamara, 20, was found in a comatose state on board the yacht last week, where it was anchored near the island of Kefalonia.

She was taken to a hospital on the island, and several hours later was transferred by helicopter to a private clinic in Athens. She died during the flight.

READ MORE: Investigation Into Death Of Australian Model On Superyacht In Greece

The circumstances surrounding her death are unclear, but the family's lawyer has asked local police to investigate.

"I declare that the family is expected from the Greek authorities to respond to the causes and circumstances of her death, the full investigation of the events and incidents that occurred prior to her death in the Mayan Queen IV yacht, in particular given the fact that the deceased had communicated by telephone with her mother and brother shortly before the unfortunate incident under investigation," said lawyer Charalampos Triantafyllopoulos.

"She was crying and referred to an incident that took place on the yacht with another crew member."

McNamara, who had been travelling through Europe and is believed to have been working aboard the yacht, was due to return home to Australia two days before her death.

"The parents also state that Sinead was not having any problems, she communicated with her family and she was happy," said Triantafyllopoulos, in a statement published by Keep Talking Greece.

"For these reasons, the family finds it crucial to thoroughly investigate both the conditions of death and the events and incidents that preceded this event in order to reveal the full truth and learn what actually happened and led their 20-year-old daughter to death."

The family is also asking why there was a long delay between the time of the "unfortunate incident" to McNamara's transfer to an Athens hospital, when she was "already for several hours unconscious, in a comatose condition and every minute was critical to her life."

Greek authorities have seized CCTV footage from the yacht, local media reports.

The yacht, the $US 140 million Mayan Queen IV, is owned by Mexican mining billionaire Alberto Baillere.

The Department of Foreign Affairs and Travel is providing consular assistance to the family.

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