Credit Suisse was convicted Monday by Switzerland's Federal Criminal Court of failing to prevent money-laundering by a Bulgarian cocaine trafficking gang, in the country's first criminal trial of one of its major banks.

A former employee was found guilty of money-laundering in the trial, which included testimony on murders and cash stuffed into suitcases and is seen as a test case for prosecutors taking a tougher line against the country's banks.

The ruling marks another headache for Switzerland's second-biggest bank, which has been reeling from billions in losses racked up via risk-management and compliance blunders.