The Swiss bank paid a huge fine in 2014 for helping clients evade taxes. Now, whistleblowers are raising questions over how closely it hewed to the settlement.

Ex-Credit Suisse bankers said that the Swiss lender broke its promise to terminate all undisclosed accounts after pleading guilty in 2014 to U.S. tax fraud, «Bloomberg» (behind paywall) reported on Sunday, citing a civil lawsuit filing.

The former bankers said that Credit Suisse failed to declare the U.S. citizenship of certain South American clients. In some cases, it continued to help them conceal assets from the U.S. tax authorities, the outlet reported. In 2014, Credit Suisse settled tax fraud allegations with the U.S. Justice Department (DoJ) for $2.6 billion.

Earlier this year the case was reopened. It isn't clear whether this was due to allegations that the bank had misappropriated funds belonging to Dan Horsky, as part of its settlement with the DoJ.

«Following our settlement in 2014, Credit Suisse has cooperated fully with U.S. authorities and continues to do so,» the bank told finews.com in an emailed statement.