Investigators have boarded an Australian cruise ship more than 10 days after the death of an elderly female passenger who was left behind on a remote island.

Suzanne Rees, 80, had been hiking on Lizard Island with fellow passengers from the Coral Adventurer, but broke off from the group for a rest. The ship left without her, only returning several hours later when the crew realized Ms. Rees was missing.

Officials from the Australian Maritime Safety Authority (Amsa) boarded the vessel on Wednesday morning local time. Amsa, which is probing the incident alongside Queensland Police and the state coroner, told the BBC it could not comment on the investigation.

The 60-day cruise around Australia, which had cost guests tens of thousands of dollars, was canceled due to Ms. Rees' death as well as mechanical issues.

The Coral Adventurer had been expected to dock at Cairns – where its operator Coral Expeditions is based. However, a lack of available berths meant it instead dropped anchor a few kilometers north early on Tuesday evening, off the coast of Yorkey's Knob, where it remained on Wednesday morning.

The ship initially left Cairns at around 07:30 local time on 24 October - after a delay of approximately a week because of mechanical issues. The next day it reached Lizard Island for the first stop on the cruise journey.

Passengers aboard were transported by tenders to the secluded island – home to a luxury resort and a research station - for a day trip with the option of hiking or snorkeling. Suzanne Rees' daughter, Katherine, said her family was 'shocked and saddened' that the Coral Adventurer left without her mother after an organized excursion.

Ms. Rees described her mother as an 'active 80-year-old' who was a member of a bushwalking group, and expressed hopes that the inquiry would pinpoint what the company should have done to ensure her mother’s safety. A search effort was conducted after Ms. Rees went missing, but her body was discovered the day after she vanished.

Mark Fifield, chief executive of Coral Expeditions, confirmed that the firm was 'working closely with Queensland Police and other authorities' to support the investigation, expressing deep sorrow over the incident.