Larry Cermak, Director of Research at The Block, revealed through a thread of tweets that the KuCoin hacker started to mix his Ethereum through 100-ETH batches on Tornado cash. He has about $4.8 million in the wallet. So far, the hacker has sent about 2,800 ETH to Tornado, but the process will likely keep going until it's all in there, he said.
Subsequently, he pointed out that the address is 0x34a17418cEC67B82D08Cf77A987941F99DC87c6b. Later, he added that this is not the first time that the KuCoin hacker used Tornado cash. This is just the first time he did it from the public address and not from the side ones.