The Federal Bureau of Investigation posted a public notice seeking any investor who thinks they've been defrauded by Bernie Madoff.

Madoff is accused of defrauding his clients out of billions of dollars. He was arrested last week on a charge of securities fraud and could serve up to 20 years in prison if convicted. Investigators estimated that clients of Madoff's investment funds, which include thousands of companies, non-profit groups and individuals, have lost approximately $50 billion because of his alleged schemes.

Read the FBI's notice below.

U.S. Department of Justice

Federal Bureau of Investigation
Press Release
26 Federal Plaza
New York, New York 10278
For Immediate Release:
December 18, 2008

U.S. v. Bernard L. Madoff

If you believe that you have been a financial fraud victim in the
above captioned matter, please provide the following information:

(1) full name
(2) mailing address
(3) phone number
(4) COPIES of any documents that substantiate your loss (do not send
original documents)

Please mail this information to:

FBI New York
ATTN: Victim Assistance Office
26 Federal Plaza
23rd Floor New York, NY 10278