German police raided the headquarters of the country's biggest lender Deutsche Bank as part of an ongoing tax fraud scam on Tuesday.

Prosecutors from Cologne searched the Frankfurt offices as part of investigations into the so-called "cum ex" case, Deutsche Bank said.

The bank added it "continues to cooperate fully" with authorities over the sprawling case, which has also ensnared Chancellor Olaf Scholz, who denies wrongdoing.

First exposed in 2017, the "cum ex" scandal involved numerous participants swiftly exchanging company shares among themselves around dividend day to claim multiple tax rebates on a single payout.

Dozens of people have since been indicted in Germany over the scam, including bankers, stock traders, lawyers and financial consultants.

German authorities have also searched other top banks over the course of 2022 in relation to the case, including Barclays, Morgan Stanley and JPMorgan Chase.

In relation to Tuesday's raids on Deutsche Bank, Cologne prosecutors confirmed they had "executed search warrants against a bank in Frankfurt" as well as against an audit firm, and in the private residences of 10 suspects.

They did not give the names of people or organizations.

In total, 114 investigators from various parts of the country took part in the search, they said.

The measures are linked to the "cum ex" investigation and related tax evasion schemes, the prosecutors said.

Authorities in Hamburg came under fire for their 2016 decision to drop a bid to claw back 47 million euros ($46 million) in taxes from private bank M. M. Warburg over the trades.

Warburg eventually had to pay back tens of millions of euros under pressure from the federal government under then-chancellor Angela Merkel.

Current Chancellor Scholz, who was mayor of Hamburg from 2011 to 2018, has been repeatedly forced to deny allegations he was involved in the decision to let the bank off the hook.