Washington: The US Federal Bureau of Investigation (FBI) has accused North Korea of orchestrating the largest crypto heist in history, stealing $1.5 billion worth of digital assets from the cryptocurrency exchange Bybit last week.

"(North Korea) was responsible for the theft of approximately $1.5 billion USD in virtual assets from cryptocurrency exchange, Bybit," the FBI said in a public service announcement.

The FBI attributed the attack to a group called TraderTraitor, also known as the Lazarus Group, which has previously been linked to cyberattacks involving North Korean interests.

According to the FBI, the group has “proceeded rapidly” in converting some of the stolen assets into Bitcoin and other virtual currencies, which have been dispersed across thousands of addresses on various blockchains. The bureau also warned that the stolen assets are likely to be further laundered and eventually converted into fiat currency.

The Lazarus Group first gained international notoriety a decade ago when it was accused of hacking Sony Pictures in retaliation for the release of "The Interview," a satirical film that mocked North Korean leader Kim Jong Un.

North Korea’s cyber-warfare programme, which began in the mid-1990s, has since evolved into a 6,000-strong cyber unit, known as Bureau 121, operating from multiple countries, according to a 2020 US military report.