Authorities have seized 320 kilogrammes of compressed marijuana, worth about 4 million baht, found floating in the sea at a bay that is part of Tarutao National Marine Park.
Park officials alerted the Satun marine enforcement command centre on Friday evening that park officials found seven big packages floating of Ao Talo Udang.
The packages were taken to the national park office, said Vice Admiral Choengchai Chomchoengphaet, commander of the Third Naval Area Command.
Investigators sent to the park office opened the packages and found they contained 320 bars of compressed marijuana, each weighing one kilogramme.
The drugs had a street value of about four million baht, said Vice Adm Choengchai. The seized drugs were handed over to the Muang Sutan police station.