Regulators: 'Possible deficiencies' in customer accounts drove MF Global to bankruptcy

As a result, the SEC and CFTC determined that a bankruptcy proceeding would be the "safest and most prudent course" for protecting customer funds and the firm's assets. Later that morning, MF Global announced it was undergoing bankruptcy.

Media reports indicate that hundreds of millions in customer funds went missing from MF Global in recent days. That disappearing cash was the reason MF Global's attempt to sell itself to another firm fell through.

Regulators were looking into whether MF Global diverted some customer funds to help prop up the company's own troubled trades, although the disappearance could simply be due to sloppy internal controls, according to The New York Times. As much as $950 million was believed to be missing initially, which had fallen to below $700 million by late Monday, with more funds expected to appear in the next few days, the paper said.