The man, identified as He Renfu, was among 30 tourists on board the Jupiter 2 tour boat, which arrived at Ao Sam, Phi Phi Island, from Phuket at about 11:30am, said Phi Phi Police Chief Lt Col Chetthapan Wichaidit.
“The boat captain, Surachai Pramongkij, 37, told us that Mr He went into the water for a swim with his life jacket on,” Col Chetthapan said.
“After five minutes of swimming, the group alerted the captain that one of the tourists had lost consciousness, that Mr He was face down in the water, motionless,” he added.
“They jumped in to help and took him [Mr He] to Phi Phi Island Hospital, but he was pronounced dead a short time later,” Col Chettapan said.
Doctors believe that Mr He suffered a pre-existing medical condition that caused Mr He to fall unconscious while swimming, Col Chetthapan said.
However, Col Chetthapan did not clarify what the “pre-existing medical condition” was.
“Tourist Police have notified the Chinese Embassy of the incident and providing assistance to the victim’s family,” he said.