More than 6 billion yen ($46.6 million) has been defrauded in scams allegedly involving four Japanese nationals currently being held in the Philippines alongside accusations they are behind a series of robberies across Japan, the country's police chief said Thursday.

Tokyo and Manila are working out details for the deportation of all four suspects as early as next week but ongoing trials in the Philippines for two of them -- Yuki Watanabe, 38, and Tomonobu Kojima, 45 -- has created uncertainty around whether they can all be deported at the same time.

The four suspects, including Kiyoto Imamura, 38, and Toshiya Fujita, 38, likely include among them the person -- or persons -- thought to have masterminded several robberies in Japan under the pseudonyms "Luffy" and "Kim" beginning from last year.

Photo taken on Jan. 30, 2023, shows a Bureau of Immigration facility in Manila. (Kyodo)

"We are making preparations to dispatch investigators so we can arrest all four swiftly, as soon as the arrangements are made," National Police Agency Commissioner General Yasuhiro Tsuyuki said in a press conference.

With President Ferdinand Marcos Jr. set to visit Japan from Wednesday, Philippine Justice Secretary Jesus Crispin Remulla has expressed his hope that the matter will be resolved.

But the Philippine government has said it cannot deport individuals who are on trial.

A lawyer for two of four Japanese nationals currently in detention in Manila who are believed to be behind a string of robberies across Japan is surrounded by journalists in the capital on Feb. 2, 2023, after their hearings were held at a local court. (Kyodo) 

A court in Manila did not drop the charges against Kojima on Thursday, with his next court hearing now scheduled for Tuesday. Watanabe has been indicted on a charge of assault and is being detained in an immigration facility in Manila following his arrest in April 2021.

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