Mt. Gox CEO Mark Karpeles is vowing not to walk away from the beleaguered exchange even as the Japanese authorities launched a full investigation into the collapse.

The documents released yesterday were "more or less” genuine said Karpeles. During a prolonged theft which had gone on for years, Karpeles said that the exchange had lost about 750,000 Bitcoins, worth an estimated $429m at current prices.

In a forum post entitled "find Mark Karpeles and do _xxxxxx- to him", one angry customer offered $10,000 for a manhunt for Karpeles if he tried to run away:

"I am just saying - if he tries to do a runner with everyone's money - I will personally hunt him down," said the customer. "The more the better - if we pool resources, time, money we have better chance of finding him - if he tries to hide."

Since the cryptocurrency is often used by nefarious persons, any loss to their income could trigger a bigger manhunt for Karpeles and the possibility that criminal gangs would likely seek revenge.

Japan's chief cabinet secretary, Yoshihide Suga, said: "I understand that ministries and agencies concerned - financial services, police and the finance ministry - are looking into the matter to learn the full scope of the issue.

"Once we have full knowledge of what happened, we will take action if necessary."