The authorities are looking into alleged kickbacks to top Canadian politicians - including former prime minister Brian Mulroney - to secure the sale of Airbus A320 aircraft worth $1.8bn to Air Canada in 1988.
One of the raids was said to have been on the home of Karlheinz Schreiber - a former aide to Franz-Josef Strauss, the former prime minister of Bavaria and Airbus supervisory board chairman, who died in 1988. Also targeted, according to German reports, were offices of Thyssen Industries and a home owned by Holger Pfahls, a former Defence Ministry official.
Airbus is a consortium which brings together British Aerospace and companies in France, Germany, Spain and Italy. It was unclear yesterday exactly why the bribery allegations should be emanating from Germany. A spokesman for Airbus said the claims were "totally unsubstantiated".
Mr Mulroney is already suing Canada's government and police for linking him to the kickback claims. Mr Schreiber also denied the allegations. German federal prosecutors believe Mr Schreiber paid Mr Mulroney and other Canadian politicians about $5m to secure the Airbus deal, according to reports.
No charges have been filed in Germany, Canada or Switzerland, where other reports said Mr Schreiber set up bank accounts for Frank Moores, former premier of the Canadian province of Newfoundland, and a second unidentified Canadian politician. Mr Moores has denied any wrongdoing.