North Korea is continuing to steal hundreds of millions of dollars from financial institutions and cryptocurrency firms and exchanges, illicit money that is an important source of funding for its nuclear and missile programs, U.N. experts said in a report quoting cyber specialists.

The panel of experts said that according to an unnamed government, North Korean “cyber-actors stole more than $50 million between 2020 and mid-2021 from at least three cryptocurrency exchanges in North America, Europe and Asia, probably reflecting a shift to diversify its cybercrime operations.”

And the experts said in the report’s section on cyber activities obtained Sunday by The Associated Press that an unidentified cybersecurity firm reported that in 2021 the North’s “cyber-actors stole a total of $400 million worth of cryptocurrency through seven intrusions into cryptocurrency exchanges and investment firms.”

These cyberattacks “made use of phishing lures, code exploits, malware, and advanced social engineering to siphon funds out of these organizations’ internet-connected ‘hot’ wallets into DPRK-controlled addresses,” the panel said, using the initials of the country’s official name, the Democratic People’s Republic of Korea.

The cryptocurrency funds stolen by the DPRK cyber actors “go through a careful money laundering process in order to be cashed out,”″ the panel of experts monitoring sanctions on North Korea said in the report to the U.N. Security Council.

A year ago, the panel quoted an unidentified country saying North Korea’s “total theft of virtual assets from 2019 to November 2020 is valued at approximately $316.4 million.”

In the executive summary of the new report, the experts said North Korea has continued to develop its nuclear and ballistic missile programs.

“Although no nuclear tests or launches of ICBMs were reported, DPRK continued to develop its capability for production of nuclear fissile materials,” the panel said. Those fissile materials — uranium or plutonium — are crucial for a nuclear reaction.

The experts noted “a marked acceleration” of North Korean missile launches through January that used a variety of technology and weapons. The experts said North Korea “continued to seek material, technology and know-how for these programs overseas, including through cyber means and joint scientific research.”

A year ago, the panel said North Korea had modernized its nuclear weapons and ballistic missiles by flaunting United Nations sanctions, using cyberattacks to help finance its programs and continuing to seek material and technology overseas for its arsenal including in Iran.