Failed Bitcoin exchange Mt. Gox has contacted Japanese police regarding the bitcoins it lost before filing for bankruptcy protection last month.
Tokyo police haven't said whether they're investigating Mt. Gox, but Japan's top government spokesman has said various agencies are gathering information about the exchange.
"Following its application for commencement of civil rehabilitation, Mt. Gox consulted with the metropolitan police department with regard to the disappearance of bitcoins which is one of the causes for said application," the Tokyo-based exchange said in a note on its website this week.
"Mt. Gox hereby announces that it has submitted necessary electronic records and other related documents," it added.
The exchange will cooperate with the authorities and try to "recover from damages," it said.
Some observers have doubted the ability of Tokyo police to unravel the complex movements of bitcoins on the exchange.
Meanwhile, the Tokyo District Court is expected to decide whether Mt. Gox can be rehabilitated or whether it must be liquidated. Mt. Gox also filed for bankruptcy protection in the U.S. this month against the background of a class-action lawsuit in Chicago alleging fraud.
Mt. Gox's lawyers were not immediately available for comment. Phone calls to the exchange's call center met with a busy signal.
Citing a software bug, Mt. Gox said in its bankruptcy application it had lost about 850,000 bitcoins, 750,000 of which belonged to customers and 100,000 of which were its own. The total value was roughly US$474 million, prompting numerous questions about what happened to the digital funds. It also said some $28 million in funds was missing.
Last week, Mt. Gox announced that it had found 200,000 bitcoins of the missing coins in an old-format digital wallet. The bitcoins were worth about $116 million, according to market prices last Friday.