“Any regulation of the bitcoin crypto-currency should involve international cooperation to avoid loopholes, Japanese vice finance minister Jiro Aichi said on Thursday. Commenting on the closure this week of Tokyo-based Mt. Gox, once the world’s biggest exchange for the bitcoin virtual currency, Aichi said the ministry would respond to the problems ‘if necessary’, after finding out exactly what happened. ‘It’s not just the Ministry of Finance; many other agencies are related,’ Aichi told a news conference. ‘As for its legal position, a currency (under Japan’s jurisdiction) would be coins or notes issued by the Bank of Japan. At the very least, we can say bitcoin is not a currency.'”
http://www.reuters.com/article/2014/02/27/us-bitcoin-mtgox-japan-idUSBREA1Q0I520140227