Palau's marine law officers have seized a Philippine vessel believed to be a mother ship of an illegal fishing fleet.
The Palau patrol boat PSS Remeliik was on its regular circuit in Palau's exclusive economic zone when it found the vessel 45 miles northwest of Helen Reef.
The Marianas Variety reports that the Gene No.8 was noticed to be moored to a fishing aggregation device, after which the marine officers boarded the vessel for an inspection.
According to their preliminary investigation, there was no valid Palau fishing permit on board, although the officers found at least 30 tons of fish onboard.
The ship's master, who was unable to produce a catch log, claimed the catch was caught in international waters.
Five Filipino crew members were detained at the marine law office and some of the catch was sold and some given away.
The boat owner has reportedly retained a lawyer in Palau to resolve the case.
Palau illegal fishing law imposes a minimum fine of $US500,000.