North Korea’s hackers have been linked with many attacks, including the 2014 Sony hack, but it looks like the totalitarian state is now targeting bitcoin, and crypto coin exchanges in particular, with its hacking teams.

That’s according to a new report from cybersecurity firm FireEye, which claims to have tracked at least five attacks on bitcoin exchanges, or individual bitcoin wallets, within the past six months. The targets reportedly include South Korea-based exchange Yapizon, and two others that were not named.

Korea’s top crypto exchange Bithumb, the world’s fourth largest exchange, was hacked in late June, while the country’s top Ethereum exchange is said to have lost over $1 million via a breach earlier this month, but it is unclear whether North Korea was involved in either heist.

The rise of bitcoin, which has surged to record highs this year and touched $5,000 per coin on some exchanges this month, and Ethereum, which has gone from $8 per coin in January to around $300 today, has made exchanges and other places were coins are stored hugely attractive targets for hackers. If figures, then, that North Korea — which already draws revenue from illicit businesses — is interested.

“It should be no surprise that cryptocurrencies, as an emerging asset class, are becoming a target of interest by a regime that operates in many ways like a criminal enterprise. While at present North Korea is somewhat distinctive in both their willingness to engage in financial crime and their possession of cyber espionage capabilities, the uniqueness of this combination will likely not last long-term as rising cyber powers may see similar potential,” FireEye concluded.