A man on the missing MAS flight from Kuala Lumpur to Beijing appears to have died while impersonating the 37-year-old Italian tourist. A second mystery man was on the flight, impersonating 30-year-old Austrian Christian Kozel.
Two other passengers now appear to have been travelling on false passports.
Officers on Phuket were checking late today whether Mr Kozel also had a passport stolen or lost on Phuket as Mr Maraldi gave an account of how his passport vanished last year.
He returned to Phuket on holiday again this year and Phuket police traced him to an apartment in Nanai Road, in the popular tourist nightlife hub of Patong.
Mr Maraldi said he arrived on Phuket on March 1 and was planning to leave on March 15. On a holiday last year, he said, he lost his passport in a deal that went wrong at a Patong motorcycle rent shop.
The woman who ran the shop told Mr Maraldi that she had given his passport to an Italian man who ''said Mr Maraldi was his husband.''
The ease with which passports can be stolen on Phuket is likely to renew criticism from international envoys who have been critical of the way passports are still being used as collateral for renting vehicles, despite their strong objections.
Mr Maraldi said the passport disappeared on July 22 last year and he went to police on July 25 to report that it had gone missing. He was able to fly back to Italy using a temporary travel document on August 3.
''I really don't have much to add,'' he said. ''I am not an expat who lives on Phuket. I have come and gone as a tourist.''
Mr Maraldi said he first learned about the disappearance of the Malaysia Airlines aircraft when his family called him to check whether he really was the Luigi Maraldi that Italian officials told them had been on the flight.
The men who disappeared on the flight using the identities of Mr Maraldi and Mr Kozel bought the flight tickets through China Airways, an MAS affiliate. One planned to travel on from Beijing to Copenhagen, while the other was headed for Frankfurt.
So far, no wreckage of the flight has surfaced and no trace of its final movements has been established.