U.S. Attorney General Eric Holder announces the results of "Operation Broken Trust." (Chip Somodevilla/Getty)

U.S. officials said Monday they have charged more than 500 people in what they dubbed the largest-ever nationwide sweep of scam artists preying on individual investors.

The announcement comes as federal agencies and the Obama administration are facing pressure to punish big-name companies and individuals for their role in the financial mess. So far, the U.S. has won few high-profile cases, compared with the aftermath of the savings and loan crisis and the dot-com bust. Get the full story »