A GAMBLER left his seat on a packed jetfoil and disappeared into the sea as the vessel sped from Macau to Hong Kong, a coroner heard. The body of Poon Ping-wong, 20, was found near Lantau on July 20, two days after he vanished from the boat. None of the passengers remembered seeing a man leave his seat or open the door. A crewman told the coroner he suspected something was wrong when he heard one of the rear doors click shut. A search of the vessel revealed an empty seat on the sold-out voyage and the crew stopped the jetfoil. Police searched the area but found no trace of the missing man. Coroner Ian Carlson yesterday returned an open verdict on Poon's death. Poon left for Macau on the morning of July 18. At nightfall, he left the gambling haven and boarded a jetfoil bound for home. 'There came a time when he left that seat and by means of one of the rear doors he stepped outside on to a small deck,' said the coroner. 'I cannot say why he did that. 'There has been a suspicion he might have done it in order to take his own life.' The coroner said it was impossible to judge whether the death was an accident or suicide. His verdict also carried a rider recommending that jetfoil staff make regular checks of the vessels' doors during journeys. He suggested that the crew members report to the ships' masters through intercom systems, and immediately report any suspicion that a passenger might have left the accommodation area.