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

The exchange's founder Sam Bankman-Fried secretly transferred $10 billion of customer funds from FTX to Bankman-Fried's trading company Alameda Research, the people told Reuters.

A large portion of that total has since disappeared, they said. One source put the missing amount at about $1.7 billion. The other said the gap was between $1 billion and $2 billion.