Pol Lt Capt Pichet Ingchaiyaphoum, a duty officer at Phe police station, said the body of Jean-Pierre Eulriet had been sent for autopsy at the Institute of Forensic Medicine at the Police General Hospital to determine the cause of death.
The 61-year-old Frenchman was found dead on the stairs to his room at Phe View Resort in Muang district in Rayong province.
A resort staff member told police that he probably died at about 4am. There was blood coming from his nose and on his left cheek and a motorcycle key was in his hand. Receptionist Chotipat Srilatala said Eulriet, whose passport said he was born in Marselle, checked in on Friday with a friend in two separate rooms.
The two went out and returned to the resort at 3am, she told Pol Lt Capt Pichet.
Police found medicines in his room. A preliminary investigation indicated he could have died from excessive alcohol or a disease, the police said.