Emanuel Agustoni, who worked for the Zurich bank from 2002 to 2005, denied wrongdoing and said he won’t travel to the US to answer the indictment obtained on Wednesday against him by federal prosecutors in Virginia.

“I will stay true to Swiss banking secrecy,” Agustoni said.

“I won’t give a single client’s name, whatever happens.”

He also accused US authorities of heavy-handed tactics, likening them to those used by Nazi Germany’s secret police, or Gestapo, in the 1930s.

Credit Suisse did not respond to a request for comment Sunday about the indictment of Agustoni, fellow Swiss Michele Bergantino and Roger Schaerer, and Italian Marco Parenti Adami, who stand accused of helping Americans hide as much as $3 billion in assets from the Internal Revenue Service.

Swiss weekly SonntagsZeitung cited unnamed bank officials as saying Credit Suisse Group is holding direct negotiations with US authorities in the case.

Two years ago the United States successfully forced rival UBS AG to hand over the names of thousands of American account holders and pay a $780 million fine.

The landmark case prompted Switzerland to soften its strict banking secrecy rules and agree to assist foreign tax authorities seeking information on their citizens’ accounts in the Alpine nation.