Three people have been accused by U.S. officials with conspiring to hack the FTX cryptocurrency exchange.
The accused, whose names have not been revealed, are suspected of stealing money from FTX using a complex SIM-swapping scam.
More than $400 million was stolen from the exchange in the incident that happened in November 2022.
The criminals use a strategy known as "sim-swapping" to trick a mobile phone company into giving them the victim's number instead of their own.
They can access important accounts and information once they gain control of the phone number and defeat security measures that rely on text message verification.
The heist happened as FTX was going through a rough patch, right before the exchange filed for Chapter 11 bankruptcy.
In November 2022, FTX and 130 of its affiliates declared bankruptcy. The company had been unable to pay out customers' withdrawals because of a bank run-style collapse caused by the theft of their funds.
Sam Bankman-Fried, the exchange's creator, was convicted on seven charges of conspiracy and fraud. His sentence hearing is set for March 28, 2024, and he might spend as much as 115 years behind bars.