An analysis showed that North Korea acquired about $400 million in virtual currency through hacking last year.
According to a report published by American blockchain analysis company Chainalysis, North Korea hacked a total of $395 million worth of cryptocurrency last year.
Hacking attacks were mainly concentrated on investment companies and exchanges, and after using phishing, malware and malicious software to steal virtual assets, North Korea stored them in a moving wallet, the report said.
The operation was primarily led by a North Korean hacking group known as the Lazarus Group, Chainalysis estimates.
Lazarus is a group believed to be affiliated with the North Korean military's General Bureau of Reconnaissance, and is included in the list of sanctions by the United States and the United Nations.
This hacker organization made its name to the international community after allegations of hacking into US Sony Pictures, which produced a film mocking the North Korean regime in 2014, surfaced.