North Korea has been using a Hong Kong-based blockchain company to launder money, according to a United Nations report.

South Korean newspaper Chosun reported that North Korea used a shipping and logistics firm called Marine China, which runs on a blockchain platform, to avoid international sanctions by laundering stolen cryptocurrency.

According to Coindesk, the quarterly report from the UN Security Council’s Sanctions Committee on North Korea claims a man named Julian Kim, under the alias “Tony Walker,” was the sole owner and investor in the firm, and had attempted to withdraw money from banks in Singapore on several occasions. Chosun reported that the UN claims the laundering scheme, which also involved another undisclosed individual linked to the firm, circulated the stolen crypto through upwards of 5,000 transactions in multiple countries to obfuscate its source.

The report further states that North Korea has developed precision “spear-phishing” attacks. Over the past three years, a previous UN report said, 17 countries have been targeted by its hacking experts resulting in over $2 billion in losses – a figure that regime has denied.

Chosun adds that the report also notes the development of malicious code used to move stolen bitcoin to a server located at Pyongyang’s Kim Il-sung University.

Severe sanctions against North Korea imposed by the UN and other international bodies have pushed the country’s regime towards cryptocurrencies over time. This September, Vice reported that the country is developing its own cryptocurrency with properties similar to bitcoin to sidestep international sanctions.

Meanwhile, North Korean intelligence services are also accused of grooming cyber agents from childhood for future careers as hackers skilled at stealing cryptocurrency, Cointelegraph reported.