CAIRO, April 24 (Reuters) - The average yields on Egypt's five-year and 10-year treasury bonds were mixed at an auction on Monday, data from the central bank showed.

The yield on the five-year bond decreased marginally to 17.221 percent from 17.232 percent at the previous auction, while the yield on a 10-year bond increased slightly to 17.135 percent from 17.134 percent.

(Reporting by Eric Knecht; Editing by Andrew Heavens) ((eric.knecht@thomsonreuters.com; +20 2 2394 8102; Reuters Messaging: eric.knecht.thomsonreuters.com@reuters.net))