At least $1 billion of customer funds have disappeared from the collapsed crypto exchange FTX, according to two people familiar with the matter.

Exchange founder Sam Bankman-Fried secretly transferred $10 billion in customer funds from FTX to Bankman-Fried's trading company Alameda Research

One source put the missing amount at around $1.7 billion. Another said the difference was between $1 billion and $2 billion.

While it is known that FTX moved customer funds to Alameda, the missing funds are reported here for the first time.

Last Sunday, Bankman-Fried had uncovered financial holes in records shared with other senior executives, according to two sources.

Bahamas-based FTX filed for bankruptcy on Friday after a rush of client withdrawals earlier this week

A hedge deal with rival exchange Binance fell through, accelerating the crypto's highest-profile collapse in recent years.

In text messages to Reuters, Bankman-Fried said he "disagrees with the characteristics" of the $10 billion transfer.

"We didn't transfer secretly," he said. "We had confused the internal labeling and misread it," he elaborated.

When asked about the missing money, Bankman-Fried replied: "???"

FTX and Almeida did not respond to requests for comment.