Federal regulators have filed civil fraud charges against former NFL cornerback Will Allen and his business partner. They're accused of reaping more than $31 million in a Ponzi scheme that promised high returns to investors from funding loans to cash-strapped pro athletes.

The Securities and Exchange Commission announced the charges Monday against William D. Allen, Susan Daub and their investment firms.

The SEC said Allen and Daub paid about $20 million to investors but received only around $13 million in loan repayments from athletes. To make up the gap they paid investors with other investors' money rather than actual profits on the investments, in a classic Ponzi scheme, the agency said.

Allen couldn't be reached for comment. A person answering the phone at Daub's home said there was no comment.