On March 23, 2022 the Ronin Network bridge (connecting Axie Infinity sidechain to Ethereum) suffered the largest cryptocurrency theft in history when attackers compromised validator node private keys, gaining control of 5 of 9 validators and using the majority to approve fraudulent withdrawals of 173,600 ETH and 25.5 million USDC ($624M total). The breach was discovered six days later on March 29.