A Korean tourist is missing after a tourist boat capsized during storms off an island in Thailand.

Hyunjin was riding the long-tailed boat called 'Pichitchai' with his friends off the 'Full Moon Party island' Koh Phangan in Surat Thani province early morning on December 29.

They were headed to Haad Yuan beach when the vessel was battered by 10ft waves that threw everyone overboard.

Police Colonel Panya Nirattimanon, superintendent of the Koh Phangan Police Station, said authorities received a distress call at 3:20 am.

He said: 'This group of passengers are all friends. They hired a long-tail boat to take them to Haad Yuan.

'When they were about 50 metres off the shore, they were struck by huge waves that caused the boat to lose balance and capsize.

'None of them were wearing life jackets, but they managed to float near the coast.'

Rescue teams were dispatched to the scene, where the passengers were struggling to stay afloat amid the harsh currents.

Thirteen people - three crew members and 10 foreign and Thai tourists - were rescued.

A Korean man, Hyunjin, was reported missing. He was on the boat with his Japanese girlfriend Miyuki Murata, with whom he had planned to open a restaurant in Thailand.

The boat operator, Pattanapong Saetiao, was found to have an expired first-class marine engine operator's licence, which had lapsed last June. He had also allegedly tested positive for methamphetamine use.

Wijak Chupharakit, director of the Koh Phangan Marine Office, said the tourist boat Pichitchai was also improperly registered and failed to comply with safety standards.

Authorities said the boat operator Pattanapong will be charged for violations under the Thai Navigation Act and for using category 1 narcotics.

The Thai Meteorological Department this weekend forecasted heavy rains and choppy seas in southern Thailand.

The agency said waves up to 10ft (three metres) during thundershowers were predicted in the Gulf of Thailand due to strong winds, while seven-foot waves were forecasted in the Andaman Sea.