The team behind Harmony Protocol is offering a $1 million reward for information leading to the return of $100 million in altcoins stolen from its Horizon bridge.

“Harmony will advocate for no criminal charges when funds are returned,” the company’s official Twitter account posted on Saturday.

On Thursday, hackers stole $100 million in Wrapped Ethereum (WETH), AAVE, SUSHI, DAI, Tether (USDT) and USD Coin (USDC), and then swapped them for Ethereum.

The Harmony team has since found the address of the hacker and is working with “national authorities and forensic specialists” to retrieve the stolen funds, according to a tweet.

Harmony also halted all Horizon bridge activity following the hack. Its native ONE token has dipped, and as of this writing was trading for $0.02445—8.5% lower than before the hack was discovered on Friday.

Harmony is a layer-1 proof-of-stake blockchain. Its Horizon bridge is a cross-chain bridge, meaning it allows users to send assets from one blockchain to another. Horizon users can move assets between Harmony’s network and Ethereum, Binance Chain, and Bitcoin. 

Hackers recently have been targeting cross-chain bridges. Qubit Finance’s bridge was hacked for $80 million back in January, thieves stole $320 million from the Wormhole bridge a month later, and hackers drained $622 million in Ethereum and USDC from Axie Infinity’s Ronin bridge in March.

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