Three Myanmar fishermen have been arrested in Thailand on suspicion of murdering a British yachtsman in a robbery attempt off southern Thailand's Andaman sea coast.

Malcolm Robertson (64) reportedly had his throat slashed in front of his wife Linda before he was thrown into the sea near Dong island, 70 kilometres off Satun province.

Authorities are still searching for his body following the attack late on Monday.

The raiders forced his wife to sail toward land, then escaped in a rubber dinghy after she tried to seek help from a passing official boat, local police captain Supalak Pongkanjana said.

Police later arrested the three men, who worked on a fishing boat based nearby, he said.

Supalak said the three had given full confessions but had only been charged with robbery and assault so far as police had not found Robertson's body.

AFP

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