An Admin-Watching Book for Layer-2 Blockchain Zksync was compromised on Tuesday, with the hacker started with $ 5 million worth of ZK-tokens.

The stolen funds were the “remaining unclaimed symbols from Zksync Airdrop,” Zksync wrote on Twitter before saying that “the necessary security measures are taken.”

The protocol’s ZK token has fallen almost 14% over the last 24 hours. Volume has risen by $ 96% to $ 71 million over the same period.

Zksync said the attack was an isolated incident and that it is limited to token air drop contract.