The Royal Thai Navy impounded another five Vietnamese fishing boats caught hunting dolphins in Thai waters.
Sailors arrested 47 crewmembers after they intercepted the five boats about 40 nautical miles off Koh Kut in Trat Province April 3.
Several dolphins were found in cold storage on the boats.
The operation came two days after the navy arrested 18 Vietnamese aboard another dolphin-fishing boat 130 nautical miles of Koh Chuang. Two other Vietnamese boats escaped that time.
The Royal Thai Navy impounded five Vietnamese fishing boats and arrested 47 crewmembers caught hunting dolphins in Thai waters.