Former Madoff chief financial officer, Frank DiPascali, will be charged by the U.S. for his participation in what is termed Wall Street's biggest investment fraud.

DiPascali was for 33 years the right hand man of swindler Bernard Madoff who is currently serving a 150-year prison sentence in a North Carolina prison.

DiPascali, 52, would be the second person other than Madoff charged in connection with the $65 billion fraud. Madoff's outside accountant, David Friehling, is also facing federal charges.

Ten or more people associated with the firm were being investigated by the FBI and could face criminal charges, a law enforcement source said in June, Reuters reported.