MF Global chief executive Jon Corzine has stepped down after the brokerage entered Chapter 11 bankruptcy.
The company applyed for bankruptcy protection on Monday after revealing £4 billion worth of eurozone debt exposure last week.
JPMorgan Chase and Deutsche Bank are the firm's two biggest creditors. The BBC reports ty are owed more than $US2 billion between them.
On Tuesday, the Commodity Futures Trading Commission and CME Group said MF Global did not separate its customers' money from its own funds.
By law, brokers have to keep their customers' money separate from other customers' money and from the company's own funds.