Keiji Nakazawa, author of "Hadashi no Gen" ("Barefoot Gen"), an iconic comic about the 1945 Hiroshima atomic bombing, has died of lung cancer at a hospital in the city, sources said Tuesday. He was 73.

Nakazawa, who died last Wednesday, based "Barefoot Gen" on his own life, telling the story of a boy who survived the U.S. atomic bombing of Hiroshima on Aug. 6, 1945.

The popular antiwar story, which was serialized in the 1970s and 1980s, is based on his experience of the atomic bombing at age 6 while on his way to school about 1.2 km from the hypocenter.

He lost his father, older sister and younger brother, and survived with his mother and older brother.

The story played a vital role in the education of Japanese youth, especially elementary and junior high school children, many of whom were introduced to the Hiroshima bombing and war through Nakazawa's work. It has also been translated in various languages, including English, French, Korean, Thai and Russian.

Hiroshima Mayor Kazumi Matsui expressed hope that the comic strip will continue to be "passed on to the next generation" and tell the horror of the atomic bombing to many people in Japan and around the world.

After publisher Choubunsha Publishing Co. released it in 1975 in the form of comic books, they were placed in school libraries. Choubunsha said it had sold more than 10 million copies as of December.

Nakazawa had battled lung cancer since it was detected in 2010. He stopped writing during his final years due to poor vision and an illness affecting his tendons.