Nov. 14 (Bloomberg) -- Katharina Wagner, the co-director of the Bayreuth Festival and great-granddaughter of the composer Richard Wagner, was in a car on the German autobahn when the driver died at the wheel, the daily Bild Zeitung reported.

Stefan Mueller, a 32-year-old lawyer for the Bayreuth Festival, suffered a heart attack while driving with Wagner from Berlin to Bayreuth yesterday, Bild reported, citing festival spokesman Peter Emmerich. Wagner, 30, managed to bring the car to a halt on the A9 highway and suffered no injuries, the paper said. Her attempts to resuscitate Mueller failed, Bild Zeitung said.

The Bayreuth Festival in September appointed Katharina Wagner and her half-sister, Eva Wagner-Pasquier, to lead the annual opera event. They succeed Wolfgang Wagner, their 89-year-old father.

To contact the reporter on this story: Catherine Hickley at chickley@bloomberg.net.

Last Updated: November 14, 2008 09:54 EST