When greater than $400 million price of crypto was mysteriously pulled out of the coffers of what was as soon as the world’s largest cryptocurrency change, FTX, on the very day that it declared bankruptcy in November of 2022, many initially suspected insiders on the firm—together with, probably, then CEO Sam Bankman-Fried, now convicted of fraud. But clues left across blockchains over the past year steered as an alternative that exterior thieves had chosen a very inconvenient second throughout FTX’s meltdown to tug off an unlimited heist.

Now, new clues revealed in a US Department of Justice indictment counsel one thing much more shocking: Some of these suspected thieves seem to have been within the United States and have now been arrested.

An indictment filed last week particulars expenses towards three individuals—Robert Powell, Carter Rohn, and Emily Hernandez—who’re accused of working a large cybercriminal theft ring. The group, which authorities say was often called the “Powell SIM Swapping Crew,” allegedly used SIM swaps—tricking telephone corporations into switching a person’s cell phone registration to the thieves’ SIM card in order that they’ll acquire entry to authentication codes despatched to the sufferer’s telephone—to steal lots of of tens of millions of {dollars} from victims’ accounts.

Most notably, the gang is accused of siphoning $400 million in digital foreign money from the accounts of an organization—named within the indictment solely as Victim Company-1—on the evening of November 11, 2022, persevering with into November 12. As first spotted by cybersecurity journalist Brian Krebs, that can be the precise timing of FTX’s theft, which the corporate itself has pegged at between $415 million and $432 million in stolen crypto.

The blockchain evaluation agency Elliptic corroborated Krebs’ inference that the $400 million theft described within the report is sort of definitely the FTX heist. “We are not aware of any other thefts from crypto businesses on this scale, on these dates,” Elliptic wrote in a blog post. “It therefore appears likely that FTX is the ‘Victim Company-1’ named in the indictment.”

FTX did not instantly reply to WIRED’s request for touch upon whether or not it’s the SIM-swapping sufferer described within the indictment.

If the indictment does, in actual fact, describe the FTX theft—and given the relative rarity of nine-figure crypto thefts and the precise timing of this one—then the charging doc reveals key particulars about how the FTX heist was pulled off. It describes how Powell allegedly requested Hernandez to focus on a particular telephone quantity for SIM-swapping. According to prosecutors, Hernandez then obtained a faux ID together with her photograph however the identify of her sufferer—probably an FTX staffer—and introduced it at an AT&T retail retailer in Texas to show her identification as she requested that the staffer’s account be transferred to her personal telephone.

That allowed the group to hijack messages supposed for the sufferer, together with authentication codes for his or her account, in response to the indictment. Given that these codes often characterize a second-factor authentication mechanism required after a person enters their username and password, it’s not clear how these different credentials may need been stolen, although cybercriminals usually get hold of them by way of phishing, credential-stealing malware, or attempting credentials leaked in different database dumps and probably reused throughout accounts.