BANGKOK - Pirates robbed a Thai tanker in Malaysian waters of some 2,000 tonnes of oil it was transporting from Singapore before planting a bomb on the vessel, Bangkok Post reported on Monday.
All 15 crew members were unharmed but the bomb remained on board the tanker Lapin after the attack on Friday, the newspaper said, citing Rear Admiral Somchai Na Bangchang, the chief of staff of Thailand's Third Naval Area Command.
The navy had sent its explosive ordnance disposal team to the ship, which was anchored roughly 11km from Pak Bara deep-sea port in Thailand's southern province of Satun, the report said.
According to the authorities cited by Bangkok Post, Lapin's captain Theekhathat Charoensuk sought help from another ship after navigating the tanker into Thai waters on Sunday.
Theekhathat said his ship was robbed in the Strait of Malacca on Friday at around 8pm, the report said.
Six to eight pirates, believed to be Indonesian, stopped the Lapin and forced the crew to surrender. Three of the pirates were armed with guns, while the others carried swords.
The pirates then manoeuvred a larger boat to the side of the tanker, before siphoning off 2,000 tonnes of bunker oil and five tonnes of diesel oil, reported Bangkok Post.
Before leaving with the stolen oil supplies, the pirates placed a device - which appeared to be a homemade bomb - on the tanker's flying bridge area.
According to the captain, the device looked like a TNT explosive and was held together by electrical wire.
The captain brought the tanker into Thai waters and anchored it between Tarutao and Lipe islands off Satun while he contacted marine police for assistance, Bangkok Post said.
Piracy in Asian waters hit its highest levels last year since a piracy watch centre started keeping tabs in 2006.
At least 169 actual or attempted sea attacks were reported last year, predominantly in Indonesia, the South China Sea, the Strait of Malacca and Strait of Singapore, according to the ReCAAP Information-Sharing Centre.
The figure overtook the previous record of 167 in 2010.