German prosecutors and tax authorities are investigating clients of Leumi as part of a probe into the bank’s alleged role in helping their wealthy clients hide money from German tax authorities through undeclared bank accounts, a German magazine reported.

Leumi said that German prosecutors are investigating bank customers that allegedly did not report to the German tax authority regarding accounts held with banks outside Germany through a Swiss branch of the Israeli bank.

The magazine reported that the probe is based on a data CD, which the State of North Rhine-Westphalia bought in late 2013 from a foreign whistle-blower.

According to the report, many wealthy people including one holding €80 million or US$110 million in assets are being targeted in the probe.

However, the Swiss officials have accused the Germans for breaking Swiss laws on banking secrecy and for executing economic espionage.