The FBI has accused the North Korean Lazarus Group of being behind the largest cryptocurrency theft in history.

"The forensic review into the targeted attack by the Lazarus Group on Bybit concluded that this attack targeted to the Bybit Safe was achieved through a compromised machine of a SafeWallet developer resulting in the proposal of a disguised malicious transaction," SafeWallet said.

It's only February but hackers have already stolen $1.6 billion in exploits, blockchain security firm Immunefi has said.