German police raided Deutsche Bank's offices in Frankfurt on Thursday in a probe of money laundering against the country's flagship lender.
Two Deutsche Bank staff members are suspected of helping clients set up off-shore businesses to launder money gained from criminal deeds.
Some 170 police officers, prosecutors and tax inspectors searched six of Deutsche Bank's offices Thursday morning, Frankfurt's public prosecutor's office said in a statement.
Numerous written and electronic business documents were seized, it added.
"We confirm that police are currently investigating our bank at various locations in Germany. The investigation concerns the Panama Papers," Deutsche Bank said in a statement, according to a CNBC translation.
"We will share more details as soon as we have them and we will cooperate with authorities," the bank added.
Shares of the bank slipped toward the bottom of the European benchmark on the news, down 3.4 percent at 4.45 p.m. London time (11.45 a.m. ET).
The public prosecutor's office in Frankfurt said an evaluation of data from the Panama Papers had triggered suspicion that the bank may have helped customers create offshore companies in tax havens around the world.
In 2016 alone, more than 900 customers with a business volume of 311 million euros ($353.6 million) were thought to have been cared for by a Deutsche Bank subsidiary based in the British Virgin Islands, the prosecutor said.
"We thought that we had provided to the authorities all the relevant information regarding Panama Papers and of course we will now cooperate closely with the prosecutors here in Frankfurt. … As it is also in our interest to clarify the facts as soon as possible," Joerg Eigendorf, global head of communications at Deutsche Bank, told CNBC's Annette Weisbach on Thursday.
"We have proven on several occasions that we have been willing to cooperate closely with the authorities when needed — and authorities even have confirmed that. We will now continue in this spirit and as soon as we have new facts we will let you know," he added.
The Panama Papers scandal refers to a leak of millions of documents to the media by Panama-based law firm Mossack Fonseca in 2016. It triggered a global scandal after showing how the rich and powerful allegedly used offshore companies to evade taxes.
The papers accused several banks of breaching money laundering laws, including Swedish lenders Nordea and Handelsbanken. Both of these banks, however, were fined for these violations in 2015 and faced no further punishment after the Panama Papers were leaked to media the following year.
After years of losses, many investors have lost faith with Deutsche Bank.
Since 2015, the lender — which once had ambitions of competing on equal terms with Wall Street's banking giants — has endured a failed stress test in the U.S., several attempts to restructure, a leadership shake-up and a ratings downgrade.
Shares of the bank have tumbled almost 50 percent this year.
Correction: This story has been updated to reflect that Nordea and Handelsbanken received no additional fines as a result of the Panama Papers.