Deutsche Bank’s Frankfurt headquarters have been raided by 170 German police officers and officials as part of a Panama Papers-related money laundering investigation.

The investigation is focused on whether Germany’s biggest bank helped clients set up offshore accounts to transfer money from criminal activities. Police and officials searched six of the bank’s offices, and have seized a number of documents, according to the prosecutor’s office.

The public prosecutor suspects two employees, aged 50 and 46 but not yet publicly identified, and other, as yet unidentified staff members may have been part of the illegal activities that involved 900 clients and transactions worth about $350 million.

Prosecutors said in a statement that Panama Papers and Offshore Leaks documents showed Deutsche Bank helped clients found offshore companies in tax havens, which were used to transfer money from criminal activity. Employees of the bank allegedly failed to report these transactions to authorities.

ICIJ’s German partners Süddeutsche Zeitung first reported on German banks’ alleged roles in money laundering in 2016.

The story was part of the Panama Papers investigation, a global collaboration of more than 370 reporters and 100 media outlets probing 11.5 million leaked files from offshore law firm, Mossack Fonseca.

Deutsche Bank issued a statement that said it had already provided authorities with “all the relevant information regarding the Panama Papers,” but that it would work with the prosecutor to “clarify the facts.”

“We will be issuing further details in due course. We are cooperating fully with the authorities,” the statement said.