FRANKFURT (Reuters) - German carmaker BMW (>> Bayerische Motoren Werke AG) and car supplier Bosch [ROBG.UL] said on Saturday they would join Deutsche Bahn [DBN.UL] in two claims for about 2.1 billion euros (2 billion pounds) in damages from air freight carriers who were involved in a cartel.

The air cargo cartel, which included Europe's biggest airline Lufthansa (>> Deutsche Lufthansa AG) and British Airways (>> International Consolidated Airlines Grp), was first discovered seven years ago and triggered fines in the European Union and in the United States.

Confirming a report in German magazine WirtschaftsWoche, spokespeople for BMW and Bosch said the companies had joined the lawsuits, announced by Deutsche Bahn in December.

The magazine also reported that Continental (>> Continental AG), Kuehne + Nagel (>> Kuehne & Nagel International AG) and Panalpina (>> Panalpina Welttransport Holding AG) were seeking damages from the cartel members, but the companies could not immediately be reached for comment.

Deutsche Bahn says its freight business Schenker was overcharged for air cargo services for more than six years as carriers colluded in setting fuel and security surcharges.

The firm is seeking 1.2 billion euros in damages plus 560 million euros in interest in a suit filed with a court in Cologne, plus another $370 million in the United States.

The airlines it is suing in Germany are Lufthansa, Air Canada (>> Air Canada), British Airways (>> International Consolidated Airlines Grp), Cargolux [CLUX.UL], Cathay Pacific (>> Cathay Pacific Airways Limited), Japan Airlines (>> Japan Airlines Co Ltd), LAN, Qantas (>> Qantas Airways Limited), SAS (>> SAS AB) and Singapore Airlines (>> Singapore Airlines Ltd.).

In the United States, it is seeking damages from Air France (>> Air France-KLM), All Nippon Airways, Cargolux, KLM, Martinair, Qantas and SAS.

European regulators fined 11 airlines involved 800 million euros in 2010 in the price fixing case, which opened the door to private claims.

(Reporting by Sabine Siebold; Writing by Harro ten Wolde; Editing by Raissa Kasolowsky)