Crypto exchanges Binance and Huobi have frozen $1.4 million in crypto tied to the Harmony Bridge heist and its alleged North Korean hackers, according to crypto tracing firm Elliptic.

In a blog post, Elliptic revealed that it provided intelligence to the two exchanges that prompted them to freeze the accounts. The funds were traced back to the $100 million hack of a “bridge” that allowed Harmony blockchain users to move crypto assets between different ecosystems.

Elliptic claimed that it followed the now-frozen Harmony funds through Tornado Cash, a privacy-focused mixing service that purports to hide one’s tracks on the public Ethereum ledger. The US sanctioned Tornado Cash because of its alleged use by North Korean hackers.

Federal investigators have credited North Korea’s infamous hacker wing, the Lazarus Group, with attacking the bridge as part of their multi-year campaign to steal hundreds of millions of crypto dollars from exchanges and infrastructure. This campaign funds North Korea’s nuclear weapons program, investigators have said.

Binance and Huobi did not immediately respond to a request for comment. The two exchanges have taken significant measures to prevent the use of their platforms for illicit activities.

The freezing of the Harmony funds is a clear example of their commitment to complying with regulations and ensuring that their platforms are not used for any illegal purposes.

Elliptic’s role in the freezing of the accounts is also significant as it highlights the increasing importance of crypto tracing firms in the fight against crypto-related crimes.

As more and more regulatory bodies start to crack down on crypto-related crimes, it is likely that firms such as Elliptic will become increasingly important in the industry.