A fuel tanker that visited Sydney with COVID-19-infected crew members aboard was allowed to leave Vanuatu without a full investigation after the body of one of the crew washed ashore there.
It has been confirmed that the dead man, whose body was found on April 11, was a middle-aged Filipino national working on the British flagged ship the Inge Kosan.
"There is no question that the circumstances are highly suspicious," local journalist Dan McGarry, a Canadian citizen, told AAP on Friday.
"So it seems extraordinary that the vessel could now be sent on its way without a conclusive investigation into how the crew member died."
The dead man had contracted the coronavirus as had 11 others in the ship's crew of 13, as confirmed by blood tests carried out in Sydney.
The blood samples were taken at Vila Central Hospital in Vanuatu's capital, Port Vila, and sent urgently to Australia.
On Friday it was confirmed that more than 10 of 15 Sydney dock workers who boarded the ship at Port Botany on March 31 had tested negative for the virus.
The remaining four dock workers are awaiting their results.
The next intended destination of the vessel, the Solomon Islands, on Friday indicated it would not allow the tanker to dock there, giving rise to concerns about the health and welfare of the crew.
The ABC reported that Vanuatu Health Minister Silas Bule had stated there was too high a risk for his small nation to treat the infected crew.
The International Maritime Organisation requires that sick or injured crewmembers are given appropriate treatment.
A spokesman for of the shipping company BW Epic Kosan told the ABC that members of the crew are asymptomatic and that the company is continuing to monitor their status.
It was unclear on Friday just where the tanker would be allowed to travel to.
Vanuatu Prime Minister Bob Loughman has said that the blood tests of 26 Vanuatu citizens, put into quarantine in Port Vila because they had contact with the body and/or the ship's crew, have all tested negative.
The Fiji Times newspaper reported on Friday that when the Inge Kosan was leaving Vanuatu, one crew member was found to be missing.
According to this version, the ship returned to Port Vila and a search operation was ordered.
However, one expatriate in Port Vila suggested that it was in fact Vanuata officials checking the crew manifest who sounded the alarm.
"I was told that crew members expressed surprise and claimed to be mystified by the man's disappearance," the expatriate said.
Australian lawyer John Malcolm, who is based in Port Vila with the law firm Geoffrey Gee Partners, and another man, found the body at a beach near Port Vila.
They pulled it ashore and called police.
Mr Malcolm told AAP that he could not see any signs of physical injuries such as cuts or bruises.
Vanuatu Prime Minister Bob Loughman on Thursday evening released the ship and lifted a COVID-19 lockdown on Vanuatu's main island, Efate, imposed after the dead sailor was found.