The crypto currency Bitcoin is being used by many in the financial industry to buy and sell items, as well as a way to hide identity.
However, a Bitcoin investment forum and one of the leading Bitcoin exchanges in Japan have both filed for bankruptcy protection, leaving the market in turmoil.
The news comes a week after the Japanese government imposed capital controls on Bitcoin withdrawals, banning them for the duration of the new year.
The Japan Securities Agency has said the two companies that filed for insolvency, Mt.
Gox and Coinbase, did not make a sufficient financial assessment of the value of the Bitcoins they held.
The loss of Mt.
Gox and Coinsafe is believed to be at least $US1bn, according to Bloomberg.
It is not known whether the losses are related to the loss of bitcoins in a cyber attack in March.
Coinbase was the second Bitcoin exchange to file for bankruptcy.
Its assets were seized in March and its chief executive, Charlie Lee, was jailed for seven months in a US federal court for failing to report a shortfall of more than $US300m.
Bitcoin prices surged when the two firms were forced to close, but have since tumbled.
The Mt.gox and Coinbase cases will be examined by the Financial Services Agency, which is overseeing financial markets.