Initial coin offering support platform KickICO lost $7.7 million in KICK tokens in a hack on Thursday, the company reported.

CEO Anti Danilevski wrote in a blog post that the startup’s team discovered some 70 million KICK tokens missing from its wallet after the KickCoin smart contract owner’s private key was compromised. Several users’ wallets were emptied as part of the hack, though the startup committed to returning tokens to all holders.

Danilevski said the firm first learned of the breach when users complained they could not find tokens worth around $800,000 in their wallets.

“In order to hide the results of their activities, they employed methods used by the KickCoin smart contract in integration with the Bancor network: hackers destroyed tokens at approximately 40 addresses and created tokens at the other 40 addresses in the corresponding amount,” Danilevski wrote.

A spokesperson from Bancor told CoinDesk that the specific function which allowed the smart contract’s private key to be compromised was built by KickICO, “and was not a prerequisite nor part of its integration of Bancor.”

The spokesperson added:

“Whether you put this capability into your token or not is totally independent from an integration with Bancor. And if you decide to build this capability into your token, you must protect it.”

Danilevski said that KickICO has restored control over the smart contract intends to return all lost tokens to users.

The platform, which launched in mid-2017, raised 5,000 ETH in a pre-ICO funding round, followed by a raise of nearly 85,000 ETH during its public token sale. The project’s partners include decentralized exchange startup Bancor as well as blockchain startups Pacatum, Coinhills and Qoin.

Correction: This article has been updated to reflect that KickICO completed its full token sale following a presale last year. It has also been updated to include a statement from a Bancor representative.

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