The Swiss bank engaged in a “pattern of obstruction” by not sharing some information during past investigations into the lender’s ties to Nazis, the Senate Budget Committee said.

A cache of client files stamped “American blacklist,” a designation for those financing or trading with Nazis or Axis partners, was recently found by investigators probing Credit Suisse, one of Switzerland’s biggest banks and now part of UBS.

Investigators looking into Credit Suisse’s connections to Nazi-era account holders uncovered new evidence that the bank failed to disclose during earlier probes, US Senate Budget Committee leaders said Saturday.

An investigation by a US Senate panel has found that troubled investment bank Credit Suisse concealed information during previous inquiries into Nazi-controlled bank accounts during World War II.