Manzarek died in Rosenheim, Germany, following a battle with bile duct cancer, the band said in a statement.
Singer Jim Morrison and Manzarek formed The Doors in 1965 after a chance meeting at Los Angeles' Venice Beach, and Manzarek's keyboard work would go on to be a touchstone of hits like "Break On Through to the Other Side" and "Light My Fire."
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"I was deeply saddened to hear about the passing of my friend and bandmate Ray Manzarek today," The Doors guitarist Robby Krieger said in a statement. "I'm just glad to have been able to have played Doors songs with him for the last decade. Ray was a huge part of my life and I will always miss him."
Manzarek, who was born in Chicago in 1939, is survived by his wife, Dorothy, two brothers, a son, daughter-in-law and three grandchildren. DM
Photo: Members of the music group "The Doors" are shown in this undated publicity photograph. Shown (L-R) are Ray Manzarek, Jim Morrison, Robbie Krieger and John Densmore. (Reuters)