This article is by Matthew Barakat of The Associated Press.

Four bankers with Zurich-based Credit Suisse Group were indicted Wednesday on conspiracy charges, accused of helping U.S. taxpayers hide as much as $3 billion in assets from the IRS.

Arrest warrants have been issued for all four, who are believed to be in Switzerland: Marco Parenti Adami, Emanuel Agustoni, Michele Bergantino and Roger Schaerer. All are Swiss citizens except for Adami, who is Italian.

Prosecutors allege in the indictment that the conspiracy goes back as far as 1953. The indictment alleges that as of late 2008 Credit Suisse was maintaining thousands of secret accounts for U.S. customers with as much as $3 billion in assets.

The indictment itself -- obtained by federal prosecutors in Alexandria, Va. -- does not specify the bank as Credit Suisse, but a law enforcement official with knowledge of the case confirmed the bank's identity to The Associated Press. The official insisted on anonymity because he was not authorized to speak publicly on the case.

Public documents unconnected to the case also identify some of the bankers as Credit Suisse employees.

Credit Suisse itself is not charged in the indictment. But the indictment states that bank officials "knew and should have known that they were aiding and abetting U.S. customers in evading their U.S. income taxes."

The indictment claims the bankers discouraged customers from participating in a 2009 amnesty program offered by the Obama administration, in which U.S. taxpayers could avoid criminal prosecution if they came forward with information on their secret accounts and agreed to pay a penalty.

In the fall of 2008, Credit Suisse began exiting the U.S. cross-border banking business, and the bankers advised clients to transfer their accounts to other Swiss banks that did not operate internationally and were therefore not subject to anything but Swiss law.

Credit Suisse spokesman David Walker said Wednesday the company is "cooperating with the authorities in their investigation of these individuals."

The Obama administration has been cracking down on foreign banks that it believes were helping U.S taxpayers hide assets. Wednesday's indictment is the first major criminal prosecution not involving Swiss-based UBS AG, which in 2009 agreed to pay a $780 million fine and turn over the names of thousands of account holders to U.S. authorities, a landmark case that breached centuries-old Swiss banking secrecy laws.

It was not immediately clear if the Swiss government would cooperate with the prosecution and turn the four bankers over for extradition. Switzerland does not normally extradite its citizens to face criminal charges in foreign countries. UBS banking executive Raoul Weil was indicted in a federal court in Florida in 2008. He was declared a fugitive in 2009, and Swiss authorities have not taken any steps to extradite him.

Copyright 2011 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

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