FRANKFURT- Deutsche Post DPWGn.DE could face losses of up to 100 million euros ($118 million) from paying service companies for the collection of letters that did not exist, a German paper reported.

Frankfurt Allgemeine Sonntagszeitung (FAS) said that the German logistics group was deceived by external services firms which charged Deutsche Post for more letters than they actually collected on behalf of the company.

"It is true that we had cases of fraud with regard to deliveries of large amounts of letters," a spokesman for Deutsche Post said, adding that prosecutors had launched an investigation months ago.

He declined to comment on the potential costs.

Three suspects have been taken into custody in relation to the case, FAS said, citing Rolf Wissen, chief prosecutor of the Koblenz prosecutors office. ($1 = 0.8480 euros)

(Reporting by Ralf Banser; Writing by Christoph Steitz. Editing by Jane Merriman) ((christoph.steitz@thomsonreuters.com; +49 69 7565 1269; Reuters Messaging: christoph.steitz.thomsonreuters.com@reuters.net))