Dresdner Bank's investment banking division plunged into the red in the third quarter as it joined the ranks of banks whose trading revenues have been hit by writedowns linked to the credit crisis.

The German bank, part of insurer Allianz, today reported a €147m ($215m) operating loss from investment banking, compared with an €88m profit in the third quarter last year. Operating revenues at the unit were down 45% at €347m, while costs were down 16% at €468m.