A glitch at a Japanese cryptocurrency exchange allowed some users to buy digital currencies for free, heightening concerns over the security of such trading platforms.
Zaif, which is run by Tech Bureau Corp, and registered by the government, said that an error occurred with its price calculation system, allowing seven users to buy some digital coins for zero yen. The exchange did not say which cryptocurrencies those were.
Six of the transactions have been voided. Zaif is trying to rectify the issue with the seventh customer who attempted to transfer the bitcoin from the exchange, a spokesperson told Reuters.
The issue was discovered on February 16 and Zaif made the public aware on February 20 via a blog on its website.
Zaif apologized and said there will be no impact on customers.
The Japanese exchange is one of the 16 that are registered with the government. Zaif's parent company had faced checks last month, according to Reuters, as regulators feared it could be vulnerable to a cyberattack.
Tech Bureau Corp has yet to respond to a request for comment when contacted by CNBC.
It comes after Japanese exchange Coincheck had over $500 million of cryptocurrency stolen last month.
Japan is one of the markets that has been quite open to cryptocurrencies, while other countries like China and South Korea have taken a tougher stance. Last year, Japan allowed merchants to begin accepting bitcoin as payment if they wanted.
The country is now looking to create regulation around the exchanges. But Reuters reported that the 16 exchanges that are currently registered with the Japanese government will create a self-regulating body that will be overseen by Japan's Financial Services Association.