KUALA LUMPUR • Four people, including three foreigners, who turned up after disappearing for over a week in the South China Sea, were found by chance after the Malaysian coast guard intercepted a trespassing Vietnamese trawler, according to officials here.

Spaniards David Hernandes Gasulla, 29, and Martha Miguel, 30, Hong Kong citizen Tommy Lam Wai Yin, 44, and Malaysian Armella Alihassan, 23, went missing on May 2 while on an island-hopping excursion in a small boat off the Malaysian state of Sabah on Borneo island.

Malaysia's coast guard and navy launched a search-and-rescue operation, but hope faded as days went by.

The quartet were unexpectedly discovered on Thursday when a Vietnamese fishing trawler was intercepted in the disputed Spratly Islands near Layang Layang atoll, for encroaching in Malaysia's territorial waters, the coast guard's First Admiral Zubil Mat Som told local media.

From the crew, the authorities learnt the four were picked up by two other Vietnamese fishing boats, he said in Sabah's capital Kota Kinabalu late on Thursday, The Star reported. The other Vietnamese ships were then contacted by radio.

"We were shocked. The woman on the radio told us she was Armella and it didn't hit me then that she was among the four missing people. It was only when she said she was with Tommy that it clicked," First Admiral Zubil was quoted as saying by Agence France-Presse news agency.

The four were said to be in good health, and photos posted on Twitter by the coast guard showed them arriving in Kota Kinabalu yesterday morning. They were to be interviewed by the authorities yesterday.

Malaysian Navy Region Two Commander Rear-Admiral Khairul Anuar Yahya said the boat capsized due to choppy seas but the four managed to turn it over. "What we understand is that they were drifting throughout the search-and-rescue operation," he told the New Straits Times.

"They suffered from sunburn but there was no major problem except for Armella, who was suffering from dehydration," he said.