About $60m worth of bitcoin and other cryptocurrencies has been stolen from Zaif, as the Japan-based company becomes the latest victim of hacks targeting cryptocurrency exchanges.

Tech Bureau, the parent company behind the Zaif exchange, admitted that close to 6,000 bitcoins, worth around $29m, had been taken by hackers. The total value of its lost assets was 6.7bn yen ($59.7m).

Two thirds of the stolen cryptocurrency, worth roughly $40m, belonged to Zaif customers.

In a statement released by the company, Tech Bureau said that its systems had been illegally accessed by hackers last Friday. Funds were transferred away from Zaif accounts over a two-hour period. However, the company failed to detect the hack until the following Monday.

It is believed that the hackers had gained access to Zaif’s hot wallets, a cryptocurrency wallet that is stored online and accessible over the internet.

The latest victim of crypto exchange hackers

The latest attack on a cryptocurrency exchange once again highlights the vulnerabilities of these platforms and the risk that you run when trusting them to look after your assets.

It comes a day after the Government of the United Kingdom described the cryptocurrency market as the “wild west”.  Members of Parliament have called for increased regulation to protect consumers. The New York Attorney General’s office issued a similar warning earlier this week.

Tech Bureau had been issued a business improvement order by Japan’s financial watchdog, the Financial Services Agency (FSA) in March. The order was issued specifically to improve security and protect against money laundering through its services.

This is the second large-scale attack on a Japanese exchange this year. In January Asia’s leading cryptocurrency exchange Coincheck lost $526m worth of cryptocurrency assets to hackers.

That was the largest dollar value stolen in one hack. However, the Mt. Gox attack in 2014, in which 850,000 bitcoins went missing, would be worth $4.1bn in today’s cryptocurrency market.

In December 2017, Reuters reported that close to 1m bitcoins had been looted from exchanges since 2011.