© Reuters / Jim Urquhart
An Australian bitcoin bank holding over US$1 million of the crypto-currency has been hacked, leaving an unknown number of users with nothing - one of the largest thefts in the currency's four-year history.
The incident took place on October 26, when the bank was hacked, with 4,100 bitcoins valued at $1.3 million stolen, the service's operator only known as 'Tradefortress' said. He refused to give his name to the press, also stressing he was not much older than 18.
It took the bank's owner two weeks to notify the affected customers.
Bitcoin is a decentralized, crypto-currency, free from any government or central bank control. Currency is sold and bought at online exchanges, and those transactions can be virtually anonymous.
One bitcoin is currently worth more than $300 on Mt. Gox, the world's largest bitcoin exchange - up from around $50 in March. There are 11,925,700 million bitcoins in circulation.
The Sydney man offered the service called Inputs.io, which he claimed was "one of the most secure web wallets on the market."
Customers were charged a small fee to keep their bitcoins there.
The site used two-factor authentication and location-based email confirmation, and said the page was started to avert "the hack of bitcoins even if the web server was compromised."
Some of the hacked money is to be refunded, the operator told Fairfax Media. Tradefortress said he would use 1,000 of his own bitcoins, as well as the money the hackers didn't steal.