(Reuters) – The United States has linked North Korean hackers to the theft of hundreds of millions of dollars worth of cryptocurrencies linked to the popular online game Axie Infinity, the US Treasury Department said on Thursday.
Ronin, a blockchain network that lets users transfer crypto in and out of the game, said digital cash worth nearly $ 615 million was stolen on March 23.
No one has explicitly blamed the hack, but on Thursday the US Treasury Department identified a digital currency address used by hackers under the control of a North Korean hacker group often referred to as “Lazarus”.
“The United States is aware that North Korea has increasingly relied on illegal activities ̵1; including cybercrime – to generate revenue for its weapons of mass destruction and ballistic missile programs as it seeks to avoid robust US and UN sanctions,” a Treasury Department spokesman said. with the initials of North Korea’s official name.
The spokesman warned that those who trade in the wallet risk being exposed to US sanctions.
Blockchain analysis companies including Chainalysis and Elliptic said the designation confirmed that North Korea was behind the burglary.
A person familiar with the matter confirmed that North Korean hackers had been the focus of the cyber security company’s investigation in recent weeks.
CrowdStrike, which was hired by Sky Mavis to investigate the intrusion, also declined to comment.
Aleksander Larsen, co-founder of Sky Mavis, which makes Axie Infinity, declined to comment.
A post on the official Ronin blog said that the FBI had attributed the hack to the Lazarus Group and that the US Treasury Department has sanctioned the address that received the stolen funds.
The United States says the Lazarus hacking group is controlled by the Reconnaissance General Bureau, North Korea’s primary intelligence agency. It has been accused of involvement in “WannaCry” ransomware attacks, hacking of international banks and customer accounts and 2014 cyber attacks against Sony Pictures Entertainment.
The United States is urging the UN Security Council to blacklist the Lazarus group and freeze its assets, according to a motion for a resolution reviewed by Reuters on Wednesday.
Hack has long plagued crypto platforms. The Ronin hack was one of the biggest cryptocurrency robberies ever.
Sky Mavis said it would use a combination of its own balance sheet funds and $ 150 million raised from investors including Binance to repay the lost money.
“We are still adding additional safety measures before redeploying the Ronin Bridge to reduce future risks,” the Ronin blog said. “Expect the bridge to be deployed by the end of the month.”
Treasury spokesman said Washington will make sure to publish cryptocurrencies guidelines to help in efforts to protect against stolen virtual currency.