Allegations of a beheading of a Fijian sailor on a fishing vessel is pointing to a wider problem of abuse on the high seas.
Fijian authorities have been searching for five crew members who jumped off the boat.
The Chinese-owned, Fiji-flagged tuna longliner FV TIRO II was found on Wednesday by a New Zealand Air Force Orion about 90 nautical miles west of Fiji, with two crew members still onboard. It later sank after taking on water.
Fisheries expert Glenn Simmons says there is a culture of silence on fishing vessels, and worries families will be left with no answers in this case.
He spoke to Corin Dann.