Sam Bankman-Fried, the former CEO of FTX, has been charged with fraud by U.S. authorities.

This follows the revelation that FTX stored private keys to its crypto wallets without encryption, leaving them vulnerable to theft.

The new CEO, John Ray III, testified that he took steps to secure more than $1 billion worth of digital assets after discovering the unencrypted private keys.

In November, wallets belonging to FTX were reportedly hacked, with estimates ranging from $300-$400 million. Bankman-Fried suggested that a “disgruntled employee” may have stolen the private keys.