Prosecutors in Frankfurt confirmed Thursday they had filed tax evasion charges against eight current and one former employee of Deutsche Bank over their alleged participation in a value-added tax fraud scheme.

They added the scheme involved a chain of transactions with carbon dioxide emissions certificates issued under a European Union trading system aimed at fighting climate change.

That system sets a ceiling on the carbon emissions of companies and power plants, which have to buy permits for additional emissions if needed, but can also sell them.

Protracted inquiry

The Frankfurt prosecutors explained those charged with fraud had used the mechanism to file incorrect VAT notifications at Deutsche's tax department in cooperation with companies unwilling to pay for their emissions, resulting in losses totaling 220 million euros ($245 million).

"Our own investigations into the matter are continuing unabated," Deutsche Bank said in a statement. "We're fully cooperating with the authorities involved."

Investigations into the tax scam started back in 2010, with some individuals outside Deutsche already convicted.

In a bid to make VAT fraud in the EU's trading scheme harder or impossible, the European Commission set up a new carbon registry doing away with national registries and creating a single platform for the trading of carbon permits.

DW