Papua New Guinea seeks the return of a Chinese-flagged fishing vessel from which a PNG fisheries observer was lost overboard in Nauru waters.
James Junior Numbaru was serving as an observer on the purse seiner Feng Xiang (feng zhiang) No. 818 when he was reported missing on Wednesday last week.
Regional media reported that when the ship docked in Nauru local police investigated and found no foul play was involved.
But PNG's National Fisheries Authority has issued a statement expressing concern at what it calls a "very unfortunate situation".
It says it has requested for the vessel to return to PNG so that both NFA and other authorities can investigate the incident.
The NFA says its immediate priority is to attend to concerns and enquiries from the observer's immediate family.
In the last few years, several PNG fisheries observers have died while on the job in the Pacific region.
At least two of the cases are considered unresolved by the Association for Professional Observers.
For the NFA, safety and protection of observers operating with the Western and Central Pacific Fisheries zone have been an ongoing concern.