South Korean spies have launched an investigation into claims that North Korea was behind the $533 million hack on the Coincheck cryptocurrency exchange.
In January, cyber crooks hacked into the exchange and made off with an estimated $533 million worth of digital cash in the form of ‘NEM tokens'.
The unidentified civil servant said South Korea's National Intelligence Service is pointing the finger of blame on the North because it has been involved in similar cases in the past.
However, the source stressed that the spy agency has not found evidence that directly implicates North Korea in the attack. Instead, the investigation is based on assumption and similar, previous events.
It is working with a range of international authorities and partners to investigate the cyber heist, added the source. However, they did not name the other countries that are taking part in the investigation, although Japan - where the cryptocurrency is based - is obviously one of them.
Over the past few years, security experts have warned about North Korea's increasing appetite for conducting cyber attacks, particularly for financial gain.
With a battered, state-controlled economy and regime of international sanctions against the state, the country has turned to various criminal activities to raise foreign currency, from money laundering to drug smuggling to, most recently, cyber crime.
It is widely believed that North Korean agencies were involved in attacks against Youbit, ultimately closing it down. It is also believed to have been behind the attacks on Bangladesh's central bank and the SWIFT international banking payments network.
Similar sources claim that South Korean cyber spies are already investigating the North's links with the high-profile hack. They believe that state hackers in the country are masterminding these attacks.
In 2014, cyber criminals hacked into the Mt. Gox exchange and stole Bitcoin to the value - then - of $470 million.
Last week, Reuters reported that Japanese authorities had warned Coincheck about a series of technical flaws before cyber criminals launched their attack.
The Japanese FSA had slapped Coincheck with a "business improvement" order, but allowed it to continue operating. It is also working on plans to currently to investigate other Japanese cryptocurrency exchanges.
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