Federal prosecutors have charged a former Chicago man of swindling nearly $8 million from more than 50 victims who were led to believe they were buying specially discounted stock in a number of well-known companies, including Google Inc., and Facebook Inc.

The U.S. Attorney's office in Chicago says 39-year-old Randy Cho, now of Newton, Mass., was charged Monday with one count of wire fraud and one count of filing a false federal income tax return. The office says Cho will be arraigned at a later date, and did not say whether he had an attorney.

Randall Samborn, a spokesman for the U.S. Attorney's office, says Cho styled himself as a self-employed securities trader while running the alleged swindle from locations in Chicago, Seattle, Boston, and Newton.