Linda and Malcolm Robertson were sailing near the island of Koh Dong
The family of a British man who was murdered and thrown off a yacht near the coast of Thailand fear his body will never be found.
Pirates are believed to have cut the throat of Malcolm Robertson of East Sussex, and then thrown his body into the Andaman 45 miles west of Satun.
The 64-year-old had been sailing with his wife Linda, near Koh Dong island, when their craft was attacked.
Thai Police have arrested three Burmese men in connection with the incident.
The migrant workers, who are said to have confessed to killing Mr Robertson, have been remanded in custody.
Mr Robertson's brother-in-law, John Clee, 63, from Battle, said: "I haven't spoken to my sister today but she sent me a text to say she was being interviewed by the police.
"They haven't found a body yet. That is our greatest fear - that they do not find his body.
"We have our fingers crossed."
He said his sister feared for her life as the men who killed her husband kept her tied up in the cabin of the 44ft yacht.
But when the thieves fled the vessel about 10 hours later Mrs Robertson was able to call to a nearby fishing vessel for help, Mr Clee said.
Police accompany Linda Robertson back to land, along with the three suspects
The couple, from Hastings, were sleeping in different parts of the boat in the early hours when people were heard on board.
Thai Police said thieves slit Mr Robertson's throat with a knife and hit him when he caught them trying to steal a dinghy from his moored yacht.
Mr Robertson was the owner of a chain of coffee shops around Hastings, but was semi-retired.
The couple, who had been married for 25 years, had two children each from previous relationships and seven grandchildren between them.
All four children were on their way to Thailand to support Mrs Robertson, who escaped with minor injuries, according to Mr Clee.
The couple had been planning to sail around islands in the Indian Ocean next January according to an advert on a sailing website.
A Foreign Office spokeswoman said the consular team in Bangkok had been in touch with their next of kin and were providing consular assistance to those involved.