Police and rescue workers went to the area and found the tourist lying unconscious on the beach after being taken off the sea by local residents and staffers of a nearby bungalow. He was given first aid, but died shortly later, Thai media reported.
Police said Spiller, his wife and their two friends had visited Koh Phangan since Feb 16. He went to swim on Wednesday amidst red flags put in front of the beach to warn about high waves.
Municipal officials and rescue workers rushed to help the 34-year-old Chinese national, whose name was withheld pending notification of relatives. He was given first aid before being sent to Koh Phangan Hospital, but later was pronounced dead.
The bodies of the two tourists were being kept at Koh Phangnan Hospital as authorities were in the process of notifying their embassies.