A third death on the coal ship Sage Sagittarius has been uncovered.
The ship first came under the spotlight in September after it was reported that two crew members had died in unusual circumstances.
The first worker, cook Cesar Llanto, disappeared from the ship while it was sailing north of Cairns.
Soon after another crewman, engineer Hector Collado, died aboard the ship just before it was due to dock in Newcastle.
Now another crew member of the ship, Japanese superintendent Kosaku Monji, has been killed while it was unloading coal, the ABC reports.
The man is understood to have been crushed in a conveyor accident.
It has been reported that the crushed worker had actually boarded the ship in Newcastle to oversee safety onboard.
According to The Herald, it took rescuers two hours to retrieve Monji's body from the conveyor belt.
This series of incidents has come to the attention of the International Transport Workers' Federation, which says the latest death is extremely suspicious, noting that it was not mentioned and only uncovered after an Australian inspector found a note in the ship's log.
"A superintendent was put on there apparently to care for the welfare and safety of the crew. This is the superintendent that met his death just recently on October 6," the ITF's Dean Summers said.
"Today is October 29; if it was a workplace accident, I would have thought any capable authority would have been able to determine that's the case [by now].
"To our knowledge that hasn't happened and the case is still under investigation, and given the past two incidents, suspicious incidents, we cannot draw a conclusion either way."
Summers went on to say that "the crew were all too scared to talk and now we have this situation of three deaths in various jurisdictions and a taskforce is needed to co-ordinate an investigation".
Image: Officer of the Watch