Deutsche Bank's offices in Frankfurt and Berlin have been raided by officials as part of an inquiry into money laundering.
In a statement, the Office of the Federal Prosecutor said it was conducting an investigation, involving the Federal Criminal Police Office, into unknown individuals and employees at Germany's largest bank.
It said Deutsche Bank had maintained business relationships in the past with foreign companies which were suspected of having been used for money laundering purposes as part of further investigations.
A Deutsche Bank spokesperson confirmed to the BBC that searches had been carried out at its premises.
Officials declined to comment on who, at the bank, or which foreign companies are being investigated.
No further information can be provided regarding the background of the business relationships, the transactions processed through Deutsche Bank AG, their scope, or the companies themselves, the prosecutor's office said.
German media has reported that the case carries possible links to Russian billionaire Roman Abramovich.
A legal representative for Abramovich told the BBC in a statement: Our client is not aware of any investigations by the German authorities in this matter.
Mr Abramovich has always acted in accordance with applicable domestic and international laws and regulations. Any suggestion to the contrary is false and defamatory, and our client reserves all rights in this matter.
Abramovich was sanctioned by the UK government and the European Union in March 2022, following Russia's full-scale invasion of Ukraine.
The oligarch, who made his fortune in oil and gas, is alleged to have strong ties to Russian President Vladimir Putin, which he denies.
Deutsche Bank is scheduled to publish its full-year results on Thursday, an announcement which will now be overshadowed by the raids.
Its shares closed nearly 2% lower on Wednesday.
It is not the first time the bank's offices have been searched.
In 2018, its Frankfurt headquarters and five other offices in the city were raided in a money laundering operation involving about 170 police and officials.
That investigation looked into whether Deutsche Bank staff helped clients set up offshore accounts to transfer money from criminal activities and was focused on activities between 2013 and the start of 2018.
