Washington, February 28 (RHC)-- A new U.S. Senate investigation finds the Swiss banking firm Credit Suisse aided tax evasion by wealthy U.S. clients who have stashed billions of dollars outside the reach of U.S. tax collectors.

The report accuses Credit Suisse of an array of tactics, from creating offshore shell entities to establishing a branch at Zurich airport where elite clients used secret elevators operated by remote control.

CEO Brady Dougan blamed the abuses on a small group of bankers at the firm. He said that despite the industry-leading compliance measures put in place -– there were "some Swiss-based private bankers who appear to have violated U.S. law."